But what if you’ve added chlorine tablets or granules and the levels won’t change? How do you raise free chlorine in a pool if you’ve already added chlorine?

If your chlorine levels are low (1 ppm) or you’re not getting a chlorine reading at all (0 ppm), shock your pool water with a chlorine-based shock.

But if your chlorine levels continue to remain low, even after shocking, you may have a high chlorine demand issue.

Keep reading for a step-by-step guide on what causes low chlorine levels and how to raise free chlorine levels in your pool.

What is Free Chlorine?

Free chlorine is the amount of chlorine that’s available to sanitize your pool water. In other words, it’s the chlorine that hasn’t been used up and is still free to kill contaminants. If there isn’t enough free chlorine in your water, bacteria and other harmful microorganisms can build up. Your free chlorine levels should be between 1 and 3 ppm.

On the other hand, combined chlorine (a.k.a. chloramines) is chlorine that’s already been used up to fight contaminants in the water. Your combined chlorine level should be no more than 0.5 ppm. If the amount of combined chlorine gets too high, your chlorine will stop working effectively and it will produce that classic chlorine smell.

Finally, total chlorine is the sum of free chlorine and combined chlorine. If the total chlorine levels are the same as the free chlorine levels (like 3 ppm), it means none of the chlorine has been used up (combined chlorine) and it’s available to work as a sanitizer.

If you’re still feeling confused about water chemistry, you’re not alone. Check out our Pool Care Video Course for a complete guide on everything you need to know about pool maintenance.

Frustrated by adding chemicals and trying to keep your pool clear all the time?

We cut out all the confusion of pool maintenance in this easy-to-read illustrated ebook and video course. It'll help you save $100 right away on pool care!

Click Here to Learn More

What Causes Low Free Chlorine Levels?

The first step in raising the free chlorine in your pool is knowing what caused it. And there are several factors that can contribute to sudden or chronically low free chlorine levels.

High Chlorine Demand

Chlorine can only sanitize so much. If you have a high bather load or a lot of debris in the water, you’ll need more chlorine to sanitize the water effectively. The more contaminants you have to fight in the water, the more chlorine your pool water will demand.

Chlorine demand is most common when your pool water sits untreated and stagnant for the winter. Heavy rainfall can also lead to chlorine demand, especially if you experience runoff from your yard.

If you just added chlorine or a chlorine-based shock to your pool and you still have a low chlorine level, there’s a chlorine demand problem.

In order to cure chlorine demand, triple shock your pool with calcium hypochlorite or cal-hypo shock. Add three pounds of shock for every 10,000 gallons of water in your pool.

Our Top Pick

Calcium Hypochlorite Pool Shock (Cal-Hypo Shock)

This fast-acting, quick-dissolving swimming pool shock from DryTec kills bacteria, controls algae, and destroys organic contaminants in pools. It comes in easy-to-use 1-pound bags.

Use the entire contents of the bag when opened. If any granules settle to the bottom of the pool use brush to disperse them. Add the right dosage of this product during evening hours while the filter pump is running.

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

Heavy Pool Use

The more swimmers you have in the pool and the more often you use it, the more contaminants your chlorine will need to fight. Things like sunscreen, dirt and even the oil from your skin can cause your chlorine to work over time.

Shock your pool weekly and especially after parties to keep your free chlorine levels high and your water sanitized.

Sunlight and Low Cyanuric Acid Levels

If you’re using unstabilized chlorine (like liquid chlorine or bleach) to sanitize your water, your chlorine levels will drop in the sunlight. That’s because the sun’s rays will break down your chlorine if it doesn’t have any stabilizer (a.k.a. cyanuric acid).

Test your cyanuric acid levels regularly and use a chlorine stabilizer to keep your chlorine from breaking down in the sunlight.

Very High Cyanuric Acid Levels

When your CYA levels are too high, it can hamper your chlorine’s effectiveness. High CYA will weaken your chlorine’s ability to sanitize your water. If you use 3-Inch chlorine tablets (trichlor pucks), it will consistently raise your cyanuric acid.

Regularly test your CYA levels and make sure that it stays within the correct range of 30 and 50 ppm.

Increased Organic Contaminants

A heavy rain storm can increase the contaminants in your pool water, And that can quickly use up your free chlorine as it binds to everything in an effort to sanitize the water.

Be sure to clean debris from your water after a storm and shock your pool, especially if you’ve experienced runoff.

Refilling the Pool with Fresh Water

If you’ve just added fresh water to your pool, it could disrupt your water chemistry. More fresh water means less sanitized, balanced water with the proper amount of pool chemicals.

Not Adding Enough Chlorine

One of the simplest reasons behind low free chlorine levels is that there’s not enough chlorine regularly added to the water. If you’re adding chlorine tablets to your skimmer but your pump shuts off, that chlorine won’t get into the water. And if you use a chlorine floater, make sure you have enough chlorine in it to cover your surface area.

Not Enough Salt in Your Salt Water Pool

If you use a saltwater generator and your chlorine levels are low, your pool may not have enough salt. Your salt cell needs a certain level of salinity to function.

Test your pool salinity every month to make sure your salt levels are within range. And be sure to regularly inspect your salt water generator to make sure it’s working properly.

How to Raise Free Chlorine in a Pool

If you’ve not cleaned your pool yet and there’s a lot of debris, your free chlorine level is likely low because it’s busy working on cleaning all the contaminants from the debris. Clean your pool and remove debris, then test the chlorine level.

Then, test your water. You’ll want to make sure your pH, alkalinity, and cyanuric acid levels are within range. If you need help balancing your water chemistry, be sure to check out our guides on pH and cyanuric acid.

Once your pool is free of debris and your other levels are balanced, it’s time to shock your water.

When you shock your pool, you’re adding enough chlorine to reach a “chlorine breakpoint.” This raises your pool’s free chlorine levels to 10 times or more over the normal amount.

There are multiple types of chlorine pool shock and each one can affect the other pool chemicals in the water, like your pH levels. Keep in mind that using a non-chlorine shock will decrease your combined chlorine but it will not raise your free chlorine level. That’s because the oxidation in a non-chlorine shock helps break up contaminents without adding chlorine.

• For Traditional Chlorine Pool Owners: Use Cal-Hypo Shock. Cal-hypo is the strongest type of chlorine shock available and will help quickly raise your free chlorine levels. Because cal-hypo shock is unstabilized chlorine, you’ll need to add it to your pool at night to avoid the sun’s UV rays destroying your shock. Then wait at least 8 hours before swimming again. But if you suspect you have high chlorine demand (lots of contaminants and a reading of 0 ppm), you’ll need to triple shock your pool.
• For Salt Water Pool Owners: Use Sodium Dichlor Shock. Dichlor shock will help raise your chlorine without causing scale buildup on your saltwater generator. But it will also raise your cyanuric acid (CYA) levels. So if you’re already dealing with high CYA levels, opt for liquid chlorine.

What if Your Free Chlorine Levels Don’t Change After Shocking?

There are several reasons why your free chlorine levels are still low after shocking your water:

• Other pool chemicals are out of balance: Without the right amount of pH or cyanuric acid in your water, your chlorine levels can fluctuate. So make sure these are balanced before shocking your pool.
• High contaminant load: You may have a build-up of bacteria or algae that requires a more aggressive shock treatment. If your pool looks dusty on the bottom or clouds up when you brush it, it’s likely mustard algae.

What if Your Free Chlorine Levels are Constantly Low?

If you find that you’re consistently getting low chlorine readings, check your cyanuric acid level. Low CYA means that your chlorine is susceptible to the sun’s UV rays. So your chlorine will burn up faster.

On the other hand, you may have high chlorine demand. Your chlorine’s effectiveness is finite. So if there are lots of swimmers or debris and organic contaminants in the water, more chlorine is required to properly sanitize the water. At a certain point, your chlorine gets used up faster than you can add it and your levels remain low. Again, shocking your pool can help fix this.

On the other hand, if you have constantly low chlorine levels in a saltwater pool, you likely need to add more pool salt or clean or replace your salt cell.

Frequently Asked Questions About How to Raise Free Chlorine in a Pool

Need more help figuring out how to raise free chlorine in a pool? Here are some common questions and answers.

What do I do if my free chlorine is too low?

If your levels are low, start by simply adding more chlorine. Then use test strips or a liquid testing kit to determine the current level. Finally, add chlorine granules to raise the levels quickly. If that doesn’t work, shock your pool.

How much shock do I need to raise free chlorine?

When shocking your pool, the goal is to significantly and quickly raise your free chlorine levels above your combined chlorine levels. So if you’re using cal-hypo shock, use 1 pound bag per 10,000 gallons of water.

Does chlorine-free shock raise free chlorine?

Non-chlorine shock will not add chlorine to your pool, and therefore, will not raise free chlorine levels. However, non-chlorine shocks will remove chloramines, a.k.a. combined chlorine.

What is more important: your free chlorine or total chlorine levels?

Both are important, but what matters is that your free chlorine levels are always higher than your combined chlorine levels. If the free chlorine level is low and the combined level is high, then you don’t have enough available chlorine to adequately sanitize your pool. Total chlorine accounts for both free and combined chlorine.

Is it safe to swim in a pool with low chlorine?

Technically, you could swim in a freshly filled pool with low chlorine. But contaminants will build up quickly in the water. So continuously using a swimming pool with a low level of chlorine could cause illness and eye or skin irritation. It’s always better to balance pool chemicals and swim in a pool with adequate chlorine.

Need More Pool Maintenance Help?

• Download our free Pool Care Cheat Sheet. It’s a free, easy-to-use guide to help you keep track of taking care of your pool.
• Subscribe to our Swim University YouTube Channel. We publish free video tutorials throughout the pool season.
• Check out our Pool Care Course. You’ll get 30+ step-by-step videos and a downloadable guide with everything you need to know about pool maintenance.

The post How to Raise Free Chlorine Levels in a Pool appeared first on Swim University®.

How long to wait to swim after shocking your pool depends on what type of shock you use: chlorine vs. non-chlorine. You can swim shortly after using non-chlorine shock in your water. But as a rule of thumb, you should wait at least 8 hours to swim after adding chlorine shock to your pool water. You’ll know it’s safe to swim if your free chlorine levels have dropped down to the normal range of 5 ppm (parts per million) or less.

So be sure to test your water before and after shocking your pool and make sure your filter is running to circulate the water after you’ve added shock.

How Long Does Shock Take to Dissolve?

Most other pool chemicals that adjust levels, like alkalinity, pH, and calcium hardness, dissolve in your pool water in under an hour. But because chlorine-based pool shock is a powerful, highly concentrated dose of chlorine, it takes longer to work in the water.

The goal of adding chlorine shock, like cal-hypo shock or dichlor, is to quickly elevate your chlorine levels. This removes algae, chloramines, and other contaminants by raising your chlorine levels above 10 ppm in a short period of time. And while that high chlorine concentration is great for killing algae and getting rid of chloramines, it’s not safe to swim in. That’s why you need to wait at least 8 hours after adding shock to your water or whenever your chlorine levels drop back to a safe range (ideally 3 ppm, or under 5 ppm). After shocking your pool, always retest your water chemistry by using either a test kit or test strips.

By the way, if you’re still feeling confused about pool chemistry, you’re not alone! Be sure to check out our comprehensive Pool Care Video Course.

Frustrated by adding chemicals and trying to keep your pool clear all the time?

We cut out all the confusion of pool maintenance in this easy-to-read illustrated ebook and video course. It'll help you save $100 right away on pool care!

Click Here to Learn More

When Should You Shock Your Pool?

Shocking helps by balancing pool water after contamination, like after a pool party or after heavy rain. It also prevents algae growth and is a more effective treatment than algaecide if you already have a significant algae bloom.

Pool shock also helps remove chloramines, or combined chlorine, and helps revitalize your existing chlorine. That means your regular chlorine can continue to do its job of sanitizer your water.

What Type of Shock Should You Use?

If you’re dealing with a significant water problem, we recommend using a chlorine-based shock, like calcium hypochlorite (cal-hypo) or dichlor shock. The powerful concentration of chlorine will help kill contaminants and algae. But because they will significantly increase the amount of chlorine in your water, your pool won’t be safe to swim in until your chlorine levels drop back down.

Our Top Pick

Calcium Hypochlorite Pool Shock (Cal-Hypo Shock)

This fast-acting, quick-dissolving swimming pool shock from DryTec kills bacteria, controls algae, and destroys organic contaminants in pools. It comes in easy-to-use 1-pound bags.

Use the entire contents of the bag when opened. If any granules settle to the bottom of the pool use brush to disperse them. Add the right dosage of this product during evening hours while the filter pump is running.

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

If you’re looking for a shock for regular maintenance or to refresh your sanitizer, use a non-chlorine shock. Also known as oxidizers, non-chlorine shocks allow you to go back to swimming shortly after it’s added to the water. That’s because it won’t affect your chlorine levels. But while this type of shock will help bring balance back to your water, it’s usually not powerful enough for pool owners dealing with major issues like algae.

Our Top Pick

In The Swim Chlorine-Free Oxidizing Pool Shock 24 x 1 Pound Bags

Powerful oxidizing agent that eliminates combined non-sanitizing chlorine (chloramines) and provides higher free chlorine levels. Helps eliminate algae growth as well as harmful bacteria. Ideal for use with chlorine or bromine sanitized applications, weekly maintenance, and will not affect other chemical levels

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

What Should You Do After Shocking Your Pool?

Once you’ve shocked your pool, allow your filter to circulate the water. Keep the pump running for at least 8 hours after shocking. And remember, always add shock at night if you’re using an unstabilized shock, like cal-hypo. Otherwise, the shock will burn off from the sun.

And if you need a step-by-step walkthrough on how to add shock to your pool water, check out our guide on How to Shock a Pool the Right Way.

Frequently Asked Questions About Shocking Pool

Need more help understanding pool shock? Here are some frequently asked questions and answers.

Can you swim in the pool after you shock a pool?

You need to wait for at least 8 hours and up to 24 hours after using a chlorine-based shock before you can swim. And you’ll want to retest your water to make sure your chemical levels are within range. If your free chlorine is at or below 5 ppm and your pH levels are at or below 7.6, it’s likely safe to swim. But always follow the manufacturer’s directions regarding wait times after adding shock.

What happens if you go in a pool that was just shocked?

If you use a pool after adding high contractions of bleach, liquid chlorine, or another type of chlorine-based shock, you may experience skin and eye damage. Chlorine shock and large concentrations of chlorine are highly corrosive. Do not swallow the water. If accidentally swallowed, seek immediate medical attention.

How long should you run a filter after shocking a pool?

Run your pool pump and filter for at least 8 hours after you shock your swimming pool. This provides adequate time for the filter to clean the water and for the pump to circulate the chemicals. If you’re treating algae, plan to run the filter for ideally 24 hours.

Is it okay to shock a pool during the day?

You can shock your pool during the day if you’re using a stabilized chlorine shock that contains cyanuric acid (such as dichlor shock). The cyanuric acid will help protect the chlorine from being destroyed by the sun’s UV rays. However, do not add a shock treatment during the day if you’re using unstabilized chlorine, like calcium hypochlorite (cal-hypo) shock. This type of shock without cyanuric acid will be destroyed by the sun. Check out our guide on the Best Shock for Your Pool for more information.

Why does the pool water turn cloudy after shocking?

It’s normal to experience cloudy water after shocking your pool. This means that the algae and contaminants are dead and suspended in the water. You can use a clarifier or flocculant to clear up your water.

How long do I need to wait to swim after adding other pool chemicals?

You can usually swim within an hour after adding other chemicals to your water. But chlorine shock needs time to circulate and dissipate. For example, if you add calcium chloride to raise your calcium levels, you should wait about an hour for the filter to completely cycle the chemical in your pool. However the dissolving time of other pool chemicals, like muriatic acid or flocculant, depend on how well it was initially mixed into the water. Always retest your water before swimming to make sure your levels are back within the appropriate ranges.

Need More Pool Maintenance Help?

• Download our free Pool Care Cheat Sheet. It’s a free, easy-to-use guide to help you keep track of taking care of your pool.
• Subscribe to our Swim University YouTube Channel. We publish free video tutorials throughout the pool season.
• Check out our Pool Care Course. You’ll get 30+ step-by-step videos and a downloadable guide with everything you need to know about pool maintenance.

The post How Long to Wait to Swim After Shocking a Pool appeared first on Swim University®.

• Light Green or Teal Green Pool Water (early-stage algae): Double shock your pool with two pounds of shock per 10,000 gallons.
• Darker Green (significant algae growth): Triple shock your pool with three pounds of shock per 10,000 gallons.
• Black Green (black algae and extreme growth): Quadruple shock your pool with three pounds of shock per 10,000 gallons.

Shocking your pool with a concentrated amount of chlorine is the most effective treatment for killing algae. An algaecide, on the other hand, is more effective at preventing algae in the first place.

What is Pool Shock and What Type Should You Use?

Shocking a pool is the process of adding a highly concentrated dose of chlorine to your swimming pool water. By quickly raising the level of free chlorine in the water, the pool shock kills algae, bacteria, contaminants, and chloramines.

There are several types of pool shocks on the market and what works well for one pool may not be the best choice for another. Here are the most common types of shock and when to add them:

Cal-Hypo Shock (Calcium Hypochlorite)

Our Top Pick

Calcium Hypochlorite Pool Shock (Cal-Hypo Shock)

This fast-acting, quick-dissolving swimming pool shock from DryTec kills bacteria, controls algae, and destroys organic contaminants in pools. It comes in easy-to-use 1-pound bags.

Use the entire contents of the bag when opened. If any granules settle to the bottom of the pool use brush to disperse them. Add the right dosage of this product during evening hours while the filter pump is running.

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

Cal-hypo shock is the strongest pool chlorine shock available. It’s the best choice for a strong treatment or if you’re combating algae. But because cal-hypo contains calcium, it can cause scale buildup in a salt generator. So if you’re a saltwater pool owner, use sparingly or consider another type of shock. You’ll also need to wait at least eight hours after shocking before you swim again. And unlike regular chlorine tablets or chlorine granules, cal-hypo shock is unstabilized chlorine. That means it’ll get destroyed by the sun’s UV rays, so you’ll need to use cal-hypo shock at night.

Dichlor Shock (Sodium Dichlor)

Clorox Dichlor Pool Shock XtraBlue (1 Pound Bags), 12 Pack

This multifunctional pool shock from Clorox comes in a 12-pack. The algae-fighting granules create crystal clear water by killing bacteria and organic contaminants. It works well for smaller pools and saltwater pools. As a dichlor-based stabilized cholorine shock, it does contain cyanuric acid.

Buy Now on Amazon

If you click this link and make a purchase, we earn a commission at no additional cost to you.

Dichlor shock has less chlorine than cal-hypo shock, but it’s still effective. You can use it for weekly treatments or to battle algae issues. Though it won’t contribute to scale buildup, it will raise your cyanuric acid (CYA) levels. Because it contains CYA, it’s stabilized and that means you can it to your pool doing the day. But you still need to wait at least eight hours before you swim again.

Non-Chlorine Shock

Our Top Pick

In The Swim Chlorine-Free Oxidizing Pool Shock 24 x 1 Pound Bags

Powerful oxidizing agent that eliminates combined non-sanitizing chlorine (chloramines) and provides higher free chlorine levels. Helps eliminate algae growth as well as harmful bacteria. Ideal for use with chlorine or bromine sanitized applications, weekly maintenance, and will not affect other chemical levels

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

Non-chlorine shock is a great option as a mild, weekly treatment. It won’t affect your calcium or cyanuric acid levels and you can swim shortly after using it. However, keep in mind that it’s not an effective way to treat severe algae problems, since it acts as an oxidizer but not a sanitizer.

Still feeling confused about water chemistry and algae problems? Check out our Pool Care Video Course for more help.

Frustrated by adding chemicals and trying to keep your pool clear all the time?

We cut out all the confusion of pool maintenance in this easy-to-read illustrated ebook and video course. It'll help you save $100 right away on pool care!

Click Here to Learn More

How Much Shock Should You Add to Your Pool?

In general, add one pound of shock to your pool for every 10,000 gallons of water. But if you’re experiencing an algae problem, you’ll need to add double, triple, or quadruple the amount of shock. Regardless, always follow the manufacturer’s instructions when adding pool chemicals to your water.

The goal is to achieve breakpoint chlorination, which is the level of chlorine needed to remove algae, contaminants, and chloramines from the water. In general, chlorine levels that reach 30 ppm mean you’ve reached breakpoint chlorination.

If you have high pH levels, high CYA levels, or high water temperatures, you’ll need a higher concentration of chlorine, and the shock may take longer to remove all the algae, bacteria, and contaminants in the water.

If your pool’s volume makes the math complicated when you’re calculating how much shock to add, consider rounding up to ensure your pool gets enough chlorine. And if you need help calculating how many gallons of water your pool holds, check out our pool volume calculator.

You should add shock when your chlorine levels are unbalanced and you need to refresh your sanitizer. Shocking your pool will increase your free available chlorine levels and decrease your combined chlorine levels.

• Free Available Chlorine: The amount of chlorine available to kill bacteria and contaminants. It should be between 1 to 3 ppm.
• Combined Chlorine (Chloramines): This is the portion of total chlorine that has reacted with the microorganisms in the water. It should be no more than 0.2 ppm.

How to Add Shock to Your Pool

There are a few steps to consider before and after shocking your pool water.

1. Test Your Pool Water

Use a water test kit or test strips to check your pool’s water chemistry. Ideally, your pool’s pH level should be balanced (between 7.4 and 7.6) before shocking to maximize the results. However, some shocks may raise your pH, so it’s okay if it’s on the lower end. Also note your CYA and Calcium Hardness levels if you’re adding shock dichlor shock (that will impact CYA) or cal-hypo shock (that will impact Calcium). The normal ranges for your water chemistry should be:

• Total Alkalinity: 100 to 150 ppm
• pH: 7.4 to 7.6
• Calcium Hardness: 180 to 220 ppm
• Cyanuric acid (CYA): 30 to 50 ppm

2. Prepare the Shock

Like all pool chemicals, always add shock to your pool water with the right protective equipment. Wear goggles, rubber gloves, and long sleeve shirt and pants to protect your skin.

The package instructions will provide guidelines for application. Some products can be added directly to your pool, while others should be mixed in a bucket of water with a wooden stick before being broadcast to your pool.

3. Add Shock to Water

Always add your shock to the deepest part of your pool first. Use a pool brush to disperse the granules to prevent them from building up in a single spot.

If you notice cloudy water, after shocking your pool, don’t panic: a cloudy pool is a sign that the algae is dead. Vacuum your pool, run your filter and consider adding a pool clarifier.

Our Top Pick

Pool Water Clarifier by Swim University

Clears cloudy pool water by combining particles making it easier for your filter to remove. Let your filter do all the work! This fast-acting formula improves filter efficiency for the more effective removal of dead algae and organic debris. Apply clarifier directly to the pool. Great for all pools including inground, above ground, concrete, plaster, vinyl liner, and fiberglass. It's also compatible with salt water, mineral, ozone, and non-chlorine pool water. 

Buy Now From Swim University

If you click this link and make a purchase, we earn a commission at no additional cost to you.

Frequently Asked Questions About Pool Shock

Need more help with adding pool shock? Here are some common questions and answers.

Can a pool be shocked too much?

Yes, it is possible to add too much shock. And if you have a smaller pool, it can take much longer for the chlorine levels to drop. Be sure to test your ph and chlorine levels afterwards and do not use the pool until the chlorine has dropped back down to 3 ppm.

How many bags of shock do I need for a 10,000-gallon pool?

This depends on the type of shock you’re using and the size of the bag. Your package directions will provide information on how much to use for your pool volume. Use more to clear up algae.

How long should you run the filter after shocking a pool?

Keep your pool filter and pool pump running for at least 6 hours after shocking your swimming pool. This provides ample time for the filter to clean the water and allows the shock a time to fully circulate within the water. If you are battling algae, run your filter after shocking for anywhere from 24 hours to a full week, depending on how much algae you have.

How long does it take pool shock to work?

Pool shock needs 12 to 24 hours to work to kill algae. Wait at least eight hours after shocking before swimming again. Test your water again 24 hours after your treatment. Once your chlorine levels are within normal range, it’s safe for swimmers again.

Should I shock my pool every week?

Yes, you should shock your pool weekly as part of regular maintenance. This helps keep contaminants out of the water and prevents algae growth from taking over. You should also shock your pool after any heavy rain, or after a pool party where you’ve had a lot of people in the water.

Does shocking a pool raise the pH levels?

Cal-hypo shock will slightly raise your pH. Non-chlorine shock will not influence your pH.

Can I use bleach or liquid chlorine to shock my pool?

Many pool owners use bleach or liquid shock in their pools. Sodium hypochlorite, a.k.a. liquid shock, is a commercial strength liquid chlorine. Containing 12.5 percent sodium hypochlorite, it’s stronger than store-bought bleach. Household bleach sold in one-gallon jugs contains 5 percent or less sodium hypochlorite. If you do use bleach to shock your pool, you’ll need to add significantly more than you would traditional pool shock to achieve higher chlorine levels.

Need More Pool Maintenance Help?

• Download our free Pool Care Cheat Sheet. It’s a free, easy-to-use guide to help you keep track of taking care of your pool.
• Subscribe to our Swim University YouTube Channel. We publish free video tutorials throughout the pool season.
• Check out our Pool Care Course. You’ll get 30+ step-by-step videos and a downloadable guide with everything you need to know about pool maintenance.

The post How Much Shock Should You Add to Your Pool appeared first on Swim University®.

Ideally, your cyanuric acid levels should be between 30 and 50 parts per million (PPM) and a bit higher if you have a saltwater pool. But if your levels are a lot higher, it may be time to lower the cyanuric acid in your pool.

In order to bring down your cyanuric acid levels, you’ll need to dilute your water by partially draining and refilling your pool. While there are other options, like cyanuric acid reducers, they’re not as effective. But before you tackle a high CYA problem, you’ll need to stop making it worse. Here’s everything you need to know about what causes high cyanuric acid levels and what you can do to lower them.

Check out the video tutorial below on how to lower your CYA levels or keep reading for a complete guide.

What Causes High Cyanuric Acid?

The most common contributor to high CYA levels is stabilized chlorine. Stabilized chlorine comes with small amounts of CYA, which helps protect your sanitizer from being destroyed by the sun.

Most chlorine tablets or chlorine granules are made with stabilized dichlor and trichlor. So if you add one pound of trichlor chlorine to a 10,000-gallon pool, it can raise the CYA level by 6 ppm. On the other hand, calcium hypochlorite (cal-hypo) chlorine, lithium hypochlorite chlorine, and liquid bleach are unstabilized. These won’t increase your CYA levels.

As you add stabilized chlorine to your water, the levels of cyanuric acid can build up over time, even as the chlorine levels fluctuate up and down. That’s because as water evaporates from the swimming pool, cyanuric acid remains in the water. So while you’re trying to bring down your cyanuric acid levels, stop adding stabilized chlorine.

Not everyone needs to worry about high CYA levels, though. If you’re a pool owner who drains and refills your pool each year or you have an indoor pool, you likely won’t need to worry about a build-up of cyanuric acid. But if you have an outdoor pool you keep open all year and you don’t get a lot of rain, you’ll need to monitor your CYA levels.

By the way, if you find pool maintenance confusing and you’d like more step-by-step help, check out our Pool Care Video Course.

Frustrated by adding chemicals and trying to keep your pool clear all the time?

We cut out all the confusion of pool maintenance in this easy-to-read illustrated ebook and video course. It'll help you save $100 right away on pool care!

Click Here to Learn More

What Happens if Cyanuric Acid Levels are Too High?

When your cyanuric acid levels are too high, it can affect your chlorine’s ability to sanitize, damage your pool and skew your water chemistry readings.

Renders Chlorine Less Effective

Too much cyanuric acid can prevent chlorine from effectively doing its job. When CYA increases, the amount of available chlorine that can sanitize the water decreases. And your free chlorine levels should be 7.5 percent of your cyanuric acid levels. So if your pool has CYA levels at 40 ppm, you’ll need to keep your free chlorine levels at 3 ppm to effectively sanitize your water. When left out of balance too long, you’ll start to see cloudy water, and may even see algae growth.

Distorts Total Alkalinity Readings

Cyanuric acid adds to your carbonate alkalinity, and that contributes to total alkalinity. So high CYA levels will return false total alkalinity readings.

Damage to Plaster Finish on Pool Walls

Typically, a high CYA concentration will mean low pH levels, since ineffective chlorine can disrupt the pH balance. This low pH will eat away at the plaster finish on your pool’s walls.

Unsanitary Water

You’ll have less chlorine available to sanitize your water when there’s too much cyanuric acid. And that means you run the risk of bacteria, algae, and contaminants building up.

How to Lower Cyanuric Acid in a Pool

Reducing cyanuric acid levels in your swimming pool isn’t an easy fix. But most importantly, stop adding more stabilized chlorine to your pool as soon as possible. This contains cyanuric acid and continuing to add it to your water will make the problem worse.

1. Dilute Pool Water by Partially Draining and Refilling

Diluting your water is the easiest and most effective way to lower cyanuric acid in your pool. This means draining some of your pool water and replacing it with fresh water. Rainwater can also help dilute your water and CYA levels, but the acidic nature of rain can upset your pool water’s balance.

Before diluting your water, test your water with test strips or a liquid test kit to determine your current CYA level. If your CYA levels are extremely high, your reading might be “off the chart” and you’ll need to take a water sample to your local pool store.

Begin partially draining your pool using a submersible pump, a hose siphon, or the waste setting on your filtration system. If you’re using your filter, set your valve to “waste” or drain. Keep in mind that you may only need to remove a few inches of water. And as you drain your pool, just make sure your water levels never reach below the skimmer. This will protect your pump from running dry.

Once you’ve drained out some of the water, refill your swimming pool with fresh water and retest your pool chemistry. Continue draining and refilling your water until you reduce cyanuric acid levels to the normal range between 30 and 50 ppm.

2. Try a Chemical Cyanuric Acid Reducer

Even though you can buy cyanuric acid reducers, they tend to be very expensive and don’t work for every pool owner. Remember, the most effective way to lower CYA is by draining and refilling with fresh water. But if you find that your CYA level is incredibly high and you can’t dilute your water, trying a CYA reducer may help.

Keep in mind that cyanuric acid reducers will not work if you’ve added clarifiers, algaecides, or phosphate treatments to the pool in the past week. You’ll also need your pool water to be at least 65°F. And your other pool chemicals, like pH and totally alkalinity, should be in range before using.

3. Use a Reverse Osmosis Filter

If you can’t dilute your water and you have chronically high cyanuric acid levels, you may want to consider purchasing a reverse osmosis filter. Pool water passes through an incredibly fine semi-permeable membrane. Then the water moves through a tank and gets filtered by activated charcoal before going back into the pool.

However, reverse osmosis wastes a lot of water and you can expect to spend a few thousand dollars for the filter and installation. It also creates water waste. With this filter, you’ll create 2 gallons of wastewater for every 1 gallon that passes through your filter.

But many pool owners find reverse osmosis filters helpful because not only will they reduce CYA, but they will also lower calcium hardness and total dissolved solids. And reverse osmosis systems are recommended in places where water shortages and restrictions are in place. So even though it wastes some water, it will save more water overall compared to an extensive pool drain and refill.

Frequently Asked Questions About Lowering Cyanuric Acid

Need more help lowering the CYA levels in your pool? Here are some common questions and answers.

How do I lower the cyanuric acid in my pool without draining it?

You don’t need to completely drain your pool to lower your cyanuric acid levels. But a partial drain and refill is the most effective way to bring down CYA. Start by partially draining the water by a few inches and adding fresh water to your pool afterward.

What causes cyanuric acid to be high in a pool?

The most common cause of too much cyanuric acid is from adding too much stabilized chlorine. In many chlorine products, CYA is included as a chlorine stabilizer. This helps slow down chlorine loss as a result of the sun’s UV rays. But as the chlorine breaks down, the CYA stays behind in the water, gradually increasing your cyanuric acid levels over time.

Is it safe to swim in a pool with high cyanuric acid?

While technically it is safe to swim in a pool with high levels of CYA, it can affect your other chemicals. Too much cyanuric acid can reduce your chlorine effectiveness, making the water unsanitary.

What if my cyanuric acid is too high?

High cyanuric acid levels can damage your pool liner, contribute to false water chemistry readings, and reduce your chlorine’s ability to sanitize. And if your water isn’t properly sanitized, you may experience cloudy water and algae issues.

Need More Pool Maintenance Help?

• Download our free Pool Care Cheat Sheet. It’s a free, easy-to-use guide to help you keep track of taking care of your pool.
• Subscribe to our Swim University YouTube Channel. We publish free video tutorials throughout the pool season.
• Check out our Pool Care Course. You’ll get 30+ step-by-step videos and a downloadable guide with everything you need to know about pool maintenance.

The post CYA Levels High? Here’s How To Lower Cyanuric Acid in a Pool appeared first on Swim University®.

While a non-chlorine shock is a great option for weekly pool maintenance, especially in smaller pools and saltwater systems, it’s not the best for every situation. So here’s everything you need to know about non-chlorine shock, its benefits, and when to use it.

What is Non-Chlorine Shock?

Non-chlorine pool shock acts as an oxidizer to remove organic contaminants, like sweat, oil, and dead skin, from your pool water. It also helps break up inorganic matter like lotion and deodorant. It’s safer to use than chlorine-based pool shock and you can swim shortly after using it.

Even without chlorine, it helps reactivate your sanitizer, removing by-products like chloramines that build up as your chlorine is used up. While there is bromine shock, the most common form of non-chlorine shock is potassium monopersulfate (MPS), which is available in powder or granular form:

Our Top Pick

In The Swim Chlorine-Free Oxidizing Pool Shock 24 x 1 Pound Bags

Powerful oxidizing agent that eliminates combined non-sanitizing chlorine (chloramines) and provides higher free chlorine levels. Helps eliminate algae growth as well as harmful bacteria. Ideal for use with chlorine or bromine sanitized applications, weekly maintenance, and will not affect other chemical levels

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

How does it differ from chlorine shock? Non-chlorine shock uses oxidization instead of sanitization to break down contaminants whereas sanitization kills bacteria. This makes non-chlorine shock a gentler option but chlorine shock a more powerful, harsher chemical. When you super chlorinate your pool with chlorine shock, the chlorine levels become incredibly high. And that makes your pool unswimmable until the chlorine reaches a safe level.

By regularly using a non-chlorine shock treatment, your regular sanitizer (chlorine) will be much more effective at maintaining clean and clean pool water. And when your sanitizer works more efficiently, you can avoid issues like algae and cloudy water.

Use chlorine-free pool shock on a weekly basis to prevent algae growth and kill harmful organic contaminants, such as bacteria.

The oxidation process in non-chlorine shock also helps reduce foaming and reduce the strain on your filters. That means needing to use less anti-foam chemicals.

By the way, if you need more help with swimming pool maintenance, be sure to check out our Pool Care Video Course.

Frustrated by adding chemicals and trying to keep your pool clear all the time?

We cut out all the confusion of pool maintenance in this easy-to-read illustrated ebook and video course. It'll help you save $100 right away on pool care!

Click Here to Learn More

Benefits of Non-Chlorine Shock

When compared to chlorine-based shock, non-chlorine shock has several advantages:

Gentler Shock Alternative

Non-chlorine shock is an effective, weekly water treatment without harsh side effects. Unlike chlorine shock, you can jump in for a swim just 15 minutes after adding it to your pool water.

However, if you have a persistent or out-of-control algae problem, the non-chlorine shock won’t do the job. You’ll need to use a chlorine shock to sanitize and kill contaminants when a non-chlorine option isn’t sufficient.

Doesn’t Raise Chlorine Levels

Using a chlorine shock will temporarily increase chlorine levels to the point where it is unsafe to swim. That means waiting at least 8-12 hours before using the pool again. But when you use a non-chlorine shock, you’re not adding any more chlorine to the water, so your levels will remain consistent. This is great for smaller pools or saltwater pools where increasing your chlorine levels too much might be a problem.

That said, it can affect your alkalinity and pH levels. If you use too much non-chlorine shock, you can cause your alkalinity and pH to decrease. And that means you may need to add something, like pH increaser, to raise the pH level back to between 7.4 and 7.6.

Won’t Raise Cyanuric Acid Levels

Certain chlorine-based shocks will raise your cyanuric acid levels. Cyanuric acid acts as a pool stabilizer to protect chlorine from the sun’s UV rays. Without a pool stabilizer, the UV rays can destroy your chlorine within a matter of hours. But, if you have too much cyanuric acid, the chlorine won’t be able to sanitize your water as effectively.

Since non-chlorine shock isn’t stabilized with CYA, you won’t have to worry about increasing cyanuric acid levels.

Won’t Alter Calcium Levels

Non-chlorine shocks also prevent fluctuations in your calcium hardness levels. Calcium is normally found in hard water supplies. And many chlorine shocks are made with calcium hypochlorite.

If the calcium level in your pool water is too high, it can lead to scale buildup on the sides of your pool, filters, and other pool equipment. It’s challenging to remove, and may permanently damage some components.

Clears Cloudy Water

As the chlorine in your pool reacts with pollutants, it becomes combined chlorine, a.k.a. chloramines. And when chloramines built up, you may notice cloudy water and even eye and skin irritation. Using a non-chlorine shock removes those pollutants and makes more free chlorine available to sanitize. Combine it with a clarifier and you can keep your water sparkling clear. Plus you can use it more often since it’s a gentler alternative to chlorine shocks.

Good for Saltwater Pools

Saltwater pools use saltwater generators to turn salt into chlorine. And that means you really don’t need to add more chlorine to the water. A non-chlorine shock keeps your water clean without altering the water’s chlorine level. Plus chlorine shocks like cal-hypo shock can cause calcium build-up in your saltwater equipment. However, it won’t be powerful enough to kill an algae bloom.

When Should You Use Non-Chlorine Shock?

While a chlorine-based shock has its place in pool and hot tub maintenance, there are many instances when you should use non-chlorine shock.

If you need to shock your pool but want to go swimming shortly after, that’s the perfect time to use a non-chlorine shock. Simply add it to your pool water according to the manufacturer’s directions and you should be ready to swim in 20 minutes or less.

If you’ve got a saltwater pool or a smaller pool, a non-chlorine shock is a great regular treatment. Because saltwater pools have a built-in chlorination system and are prone to calcium buildup, you’ll want to avoid chlorine shocks with calcium hypochlorite. And it can be difficult to bring down super high chlorine levels in smaller pools, so a non-chlorine shock is best here too.

You’ll want to keep your chlorine levels at 1 to 3 parts per million (PPM) or a bit higher in saltwater pools. At 5 ppm or higher, swimmers may start to experience eye and skin irritation. 10 ppm or higher is the usual level for a chlorine-based shock.

If you have cloudy water, a shock oxidizer or non-chlorine shock can be a helpful easy, remedy. You can also add a non-chlorine shock to your pool or spa water between chlorine shocks.

But a non-chlorine shock will not work if you have a serious pool water problem, like algae. You’ll need a more powerful, chlorine-based shock (like cal-hypo shock) to handle problematic pool water.

How to Shock Your Pool With Non-Chlorine Shock

Even though it’s not as harsh as chlorine, you should still take some safety precautions when using non-chlorine shock.

Always wear gloves, protective eyewear, and adequate clothing when working with water treatment chemicals. For most non-chlorine shocks, you can broadcast it directly into a pool. But if you’d like to pre-mix your shock to avoid any wind blowing shock outside of your pool, you can do that as well. Just always follow the manufacturer’s dosing instructions.

If you want to pre-mix your shock, add the shock into a five-gallon bucket of water and stir with a wooden spoon. Then, pour the shock solution around the pool’s perimeter. Set a timer for 15 minutes. Once it goes off, your water is ready!

Frequently Asked Questions about Non-Chlorine Shock

Need more help with non-chlorine shock? Here are some commonly asked questions and answers.

Can I shock a pool with no chlorine in it?

Your pool needs a sanitizer, like chlorine, to kill bacteria and prevent algae buildup. If you need to shock a pool that has no chlorine, use a chlorine-based shock.

Does non-chlorine shock raise chlorine levels?

No, non-chlorine shock will not raise chlorine levels. It can, however, affect the pH balance. The average pH of non-chlorine shock is 2.3, which can bring your pH out of its normal range (7.4 to 7.6).

How long does a non-chlorine shock last?

A non-chlorine shock is great as a weekly treatment, but it won’t continuously sanitize your pool or kill algae. You’ll still need to add a sanitizer like chlorine to your water. And on occasion, you may need to use chlorine shock.

How long does it take for a non-chlorine shock to work?

Non-chlorine shock starts working immediately by boosting the effectiveness of your sanitizer in your water. And it’s safe to enter the water within 15 to 20 minutes after adding it to the pool.

Can you use too much non-chlorine shock?

Yes, you can use too much non-chlorine shock. If you use too much, the overall pH level of your pool will drop for an extended period of time. You’ll have to fix it by adding another chemical like sodium carbonate (soda ash) or sodium bicarbonate (baking soda) to raise the pH level.

Need More Pool Maintenance Help?

• Download our free Pool Care Cheat Sheet. It’s a free, easy-to-use guide to help you keep track of taking care of your pool.
• Subscribe to our Swim University YouTube Channel. We publish free video tutorials throughout the pool season.
• Check out our Pool Care Course. You’ll get 30+ step-by-step videos and a downloadable guide with everything you need to know about pool maintenance.

The post Non-Chlorine Shock: Is It Better For Your Pool Than Chlorine? appeared first on Swim University®.

Not all pool shock products are right for every type of pool or for every pool situation. In general, we recommend the following pool shock:

• Cal-hypo shock: Use this if you have algae issues or if you want a powerful, weekly treatment. You will need to use this at night and wait at least 8 hours before swimming. Be careful using it in saltwater pools, since it can cause scale build-up in the saltwater generator by increasing your calcium hardness levels.
• Dichlor shock: A little less powerful than cal-hypo shock, but still effective. Use this for weekly treatments or algae issues in saltwater pools. This will not cause scale build-up but it will raise your cyanuric acid levels. You can add it during the day since it’s stabilized, but you’ll still need to wait at least 8 hours before you swim.
• Non-chlorine shock: Use this as a weekly treatment or if you want to swim shortly after shocking. It won’t affect your calcium or CYA levels, but it can affect your pH. This is not effective at tackling larger issues like algae.

Want more help picking out the best pool shock for your pool? Check out our video below. Or keep reading for a breakdown of how pool shock works, the different types of pool shock, and when to use each one.

How Does Pool Shock Work?

When you shock your pool, you’re adding enough chemicals (usually chlorine) to clean the water and remove the chloramine buildup. These chloramines build up when chlorine mixes with urine, sweat, the oils in our skin, and nitrogen. It’s a naturally occurring chemical process that happens when your chlorine does its job. But it’s what gives a pool that chlorine-like smell.

If you’ve ever visited a hotel pool or to the gym for a quick workout and smelled lots of chlorine, you’ve actually come across an improperly sanitized pool. That strong chlorine odor is a result of the buildup of chloramines in the water, not an indication that the pool itself is clean.

What Are The Best Types of Pool Shock?

Cal-Hypo Chlorine Shock

In The Swim Cal-Hypo Non-Stabilized Pool Chlorine Granules - 25 lbs.

Buy Now

If you click this link and make a purchase, we earn a commission at no additional cost to you.

Calcium hypochlorite shock, or cal-hypo shock, is the most powerful shock treatment for both regular pool maintenance and problematic pool water.

Found usually in granule form, cal-hypo shock is readily available, affordably priced, and straightforward to use. Some versions can be broadcasted directly into your water or you may be required to pre-dissolve it before adding it to your pool.

You can find varieties that contain anywhere from 65% to 75% chlorine. However, it will affect your other chemical levels. Because cal-hypo contains calcium, it can cause scaling and calcium build-up. And it will also raise your water’s pH levels, so if the pH is high after shocking, you’ll need to balance it. However, it is unstabilized chlorine, meaning it does not contain cyanuric acid and it won’t increase your CYA levels.

Cal-hypo shock should only be used at night because it’s unstabilized chlorine and the sun’s UV rays can burn away. Simply add the pool shock to your water at dusk, circulate your water and check your pool the next day.

Dealing with algae or green pool water? Cal-hypo is the best shock treatment for you. It’s powerful enough to kill contaminants and stop algae growth (similar to an algaecide). However, it may require multiple doses, depending on your situation.

It’s a powerful weekly treatment for your pool, especially if you deal with ongoing green water or cloudy water. However, it’s not suitable for saltwater pools, hot tubs, or even smaller-sized pools. Always follow the manufacturer’s instructions and pay attention to the guide on the package.

Dichlor Shock

Clorox Dichlor Pool Shock XtraBlue (1 Pound Bags), 12 Pack

This multifunctional pool shock from Clorox comes in a 12-pack. The algae-fighting granules create crystal clear water by killing bacteria and organic contaminants. It works well for smaller pools and saltwater pools. As a dichlor-based stabilized cholorine shock, it does contain cyanuric acid.

Buy Now on Amazon

If you click this link and make a purchase, we earn a commission at no additional cost to you.

Also known as sodium dichloro-s-triazinetrione or sodium sichlor, dichlor shock can be used for both shock treatments and regular chlorine doses.

Unlike cal-shock, it contains only 50% to 60% chlorine and is made with stabilized chlorine so it won’t burn off in the sun.
But that means it will add 0.9 ppm of cyanuric acid for every ppm of additional free chlorine. So avoid using this kind of pool shock if your water test kit shows higher than normal cyanuric acid levels.

Most brands can be added directly to your pool, but a few must be dissolved first. And after adding it to your pool water, you’ll need to wait 8 hours before swimming again.

You can also find lower percentage dichlor products (15% to 20%) that work as “shock-and-swim” options. These typically let you swim about 15 minutes after treating your pool, but you should always read the label and follow the instructions.

Non-Chlorine Shock

Our Top Pick

In The Swim Chlorine-Free Oxidizing Pool Shock 24 x 1 Pound Bags

Powerful oxidizing agent that eliminates combined non-sanitizing chlorine (chloramines) and provides higher free chlorine levels. Helps eliminate algae growth as well as harmful bacteria. Ideal for use with chlorine or bromine sanitized applications, weekly maintenance, and will not affect other chemical levels

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

If you want to shock your pool and swim soon after, a non-chlorine shock is your best option. Opting for this potassium mono sulfate shock gives you a gentler pool shock alternative without affecting your other chemistry levels.

You can add non-chlorine shock to your pool water anytime day or night. And since it’s both fast-acting and gentle, you can safely swim again after about 20 minutes. This is also a great option for smaller, above ground pools since traditional chlorine shock takes longer to dissipate.

Looking to kill the algae in your pool? Unfortunately, a non-chlorine shock isn’t powerful enough to eliminate green water and algae growth. And this type will only work if there’s a chlorination system present within the pool. This is the preferred way to shock a saltwater pool or a hot tub.

By the way, if you need more help keeping your pool clean and clear, check out our pool maintenance video course.

Frustrated by adding chemicals and trying to keep your pool clear all the time?

We cut out all the confusion of pool maintenance in this easy-to-read illustrated ebook and video course. It'll help you save $100 right away on pool care!

Click Here to Learn More

What to Consider When Choosing Your Pool Shock

Saltwater vs. Traditional Pool

The difference between a traditional pool and a saltwater pool is simple: you’re adding salt to one and adding chlorine to the other. But a saltwater pool and chlorine pool both contain chlorine. That’s because the salt in a saltwater pool is converted into chlorine by a salt-chlorine generator.

Because of this, adding a high-chlorine shock to your pool could easily over-chlorinate your water and throw off the chemical balance. And cal-hypo shock is notorious for causing scale build-up in saltwater pools.

That’s why it’s best to use either dichlor shock or non-chlorine shock for regular saltwater pool maintenance and cal-hypo shock for algae issues. Even saltwater pools need to be shocked every week or two (and more often if there’s been heavy rain or high usage). But if your saltwater generator has a “super chlorinate” option, you can use that to increase the chlorine in the water which would effectively shock your pool.

Granule vs. Liquid vs. Tablet Shock

Pool shock is available in several forms: granule, liquid, and tablet.

• Granular or powder pool shock is generally sold in 1 pound bags or a bucket. Depending on the brand, you can add these powder or granules directly to the pool water or premix them. Always follow the manufacturer’s instructions before any pool chemicals. Expect it to take anywhere 8 to 24 hours before the pool is safe to swim in again.
• Liquid pool shock is added directly to the pool water. That means there’s no need to wait for anything to dissolve. Most commonly, liquid treatments are made with concentrated sodium hypochlorite solution. This chemical can burn your skin and damage your clothing so be careful when you measure and pour it. Liquid products are often less expensive than powder equivalent. But sometimes they’re less potent, too. Follow the manufacturer’s directions and add the recommended amount for the gallons of water in your pool.
• Tablet pool shock is the slowest option. Your tablet may take up to 2 hours to completely dissolve in the water. It can take up to 48 hours for the pool to be safe to swim in.

Stabilized vs. Unstabilized Shock

Unstabilized shock doesn’t have cyanuric acid added to it. Pool shock with CYA stabilizes the chlorine to make it last longer in the pool and in the sunlight. Without the added acid, the UV rays break down the chlorine, making it less effective.

If you want to shock your pool without affecting your CYA levels, use shock without added cyanuric acid (like cal-hypo shock). Just be sure to shock it at night when the sun won’t burn up the unstabilized chlorine.

How Much Chlorine You Need

For a regular weekly pool shock, you might not need a high concentration of chlorine. However higher chlorine levels are necessary for treating green water, problematic pools, or sanitizing after lots of swimmers have been present.

Each type of pool shock has different levels of chlorine:

• Cal-hypo contains 50% to 80%
• Sodium dichlor shock contains 40% to 50%
• Non-chlorine shock (potassium monopersulfate) contains no chlorine but will reactivate any available chlorine molecules present in the water.

pH Levels

Chlorine-based pool shock will always alter the pH level of your pool. But non-chlorine shock won’t.

Check the pH level after you add the shock and check it again before getting into the pool to make sure your pH level has returned to normal.

Your pool’s ideal pH level should be anywhere between 7.4 to 7.6, with 7.5 being ideal. If the pH level is too high, the water is too basic, or alkaline. This can lead to eye irritation – swollen, itchy, red eyes are nobody’s idea of fun. When the pH falls too low, the water becomes too acidic which leads to skin irritation – itching, burning, and rash.

If you need help balancing your pH levels, check out our guide to Basic Pool Chemistry 101.

Dissolving Time

When using a liquid pool shock, you won’t need to worry about dissolution time. But, if you opt for a tablet or a powder treatment, you should consider the dissolving time when you plan to shock your pool.

Powders are quick-dissolving. But they may require premixing to prevent damage to vinyl pool liners. Tablets, on the other hand, take the longest to completely dissolve.

Never swim while the tablet is dissolving and follow all of the manufacturer’s directions about swim time. And after you shock your pool, check the pH balance to make sure the water is safe before diving in.

Algae Problems

Even pool owners who take excellent care of their pool water deal with algae issues. And some shocks are better than others at clearing up your water.

Cal-hypo shock is an effective way to handle algae growth and destroy organic contaminants. But how much you use depends on what kind of algae you’re up against.

• Green Algae: Use a double dose of pool shock
• Yellow or Dark Green Algae: Use a triple dose of pool shock
• Black Algae: Use a quadruple dose of pool shock

Frequently Asked Questions about Pool Shock

Have more questions about picking out the right pool shock for your swimming pool? Here are some common questions and answers.

What is the best pool shock treatment?

The most effective pool shock treatment depends on your pool’s condition and the type of pool you have. Our top pick for the most powerful pool shock is cal-hypo shock. But non-chlorine shock is the most gentle and won’t affect your other chemistry levels.

What type of shock should I use in my pool?

The type of pool shock you should use depends on the type of pool you have and why you’re shocking your pool. If you’re dealing with algae or a build-up of organic contaminants, use cal-hypo shock. If you’re shocking as part of regular pool maintenance, it’s fine to use any type of shock. Just know that dichlor shock will raise your cyanuric acid levels. And if you have a saltwater pool, the best shock treatment is with either a dichlor shock or a non-chlorine shock. You can use cal-hypo shock for algae issues, but it can raise your calcium levels.

Is pool shock all the same?

No, in fact, there are three main types of pool shock – calcium hypochlorite, sodium dichloro-s-triazinetrione, and potassium monopersulfate. Each one is used for a different reason and in different pools.

What is the difference between shock and super shock for pools?

The difference between these two kinds of pool shock comes down to the concentration of calcium hypochlorite. A super shock treatment is more concentrated than the standard version.

Is liquid chlorine better than pool shock?

Pool shock and liquid chlorine are chemically the same but they have extremely different concentrations of chlorine. You will need to add significantly more liquid chlorine than you would cal-hypo shock if you want to oxidize chloramines in your pool.

Are pool shock and chlorine the same thing?

No, they are similar but aren’t the same thing. Shock has a much higher concentration of chlorine compared to chlorine sanitizers.

How often should you shock your pool?

Shock your pool once a week during the pool season to help keep algae at bay and kickstart your sanitizer. If you have a rainstorm or lots of people using your pool, shocking more often may be necessary.

Can I over shock my pool?

Adding too much shock can disrupt the chemical balance in your pool water. You may notice cloudy water and you won’t be able to use your pool before it clears up. If you’re still having issues with cloudy water after a few days, consider using a pool clarifier or pool flocculant.

Occasionally adding too much shock won’t be an issue, but do it too often and you risk damaging your pool equipment or your vinyl liner. Pool shock impacts your pH levels. And low pH can cause pool equipment corrosion. If it’s too high, scale may build up on your equipment and pool walls.

Can I use bleach in my pool?

While bleach does contain the active ingredient chlorine, it’s in a lesser concentration than in most pool shock products. It’s not recommended to use bleach in place of a shock. If you add bleach, you risk damaging your pool and causing health issues, especially if you’re using other pool chemicals to balance your pool water chemistry.

Need More Pool Maintenance Help?

• Download our free Pool Care Cheat Sheet. It’s a free, easy-to-use guide to help you keep track of taking care of your pool.
• Subscribe to our Swim University YouTube Channel. We publish free video tutorials throughout the pool season.
• Check out our Pool Care Course. You’ll get 30+ step-by-step videos and a downloadable guide with everything you need to know about pool maintenance.

The post What’s the Best Pool Shock for Your Swimming Pool? appeared first on Swim University®.

What is Pool Shock?

Pool shock is a chemical that oxidizes chloramines in your pool water. “Shocking” your pool is also a process called superchlorination. By shocking your pool, you’re adding enough chlorine (or another chemical) to sanitize the water and destroy the buildup of chloramines.

Chloramines form when chlorine mixes with the nitrogen in sweat, oils, and urine. This is a natural chemical process, basically a byproduct of your chlorine doing its job.

Think back to the last time you walked past a hotel pool. The strong chlorine smell actually comes from chloramines, a sign of improperly sanitized water.

Shocking your pool can also help clear up cloudy water and kill pool algae growth if your pool is green.

Also, if you’re looking for more help on taking care of your pool, we’ve created a full video course covering everything you need to know about your pool, how to clean it properly, and strive to make water chemistry super easy for you. Check out our Pool Care Video Course and Handbook today!

Frustrated by adding chemicals and trying to keep your pool clear all the time?

We cut out all the confusion of pool maintenance in this easy-to-read illustrated ebook and video course. It'll help you save $100 right away on pool care!

Click Here to Learn More

Types of Chlorine

Before we dive into how to shock a pool, you first have to understand the difference between total and free chlorine, and combined chlorine and breakpoint chlorination.

• Free Chlorine (FC) is the amount of pool chlorine actively disinfecting your water. You want your water’s FC level to be between 1 and 3 parts per million (ppm) so the chemical can do its job.
• Combined Chlorine (CC) is the amount of chlorine that’s been used. It’s still in the water, but its sanitizing power is greatly diminished. You want to keep your CC level at less than 0.2 ppm.
• Total Chlorine (TC) is the sum of FC and CC in your pool. Pool water testing kits can measure the FC and TC of your water. To find the CC of your pool, simply subtract the FC from your TC.
• Breakpoint Chlorination is when you have enough FC to shatter the molecular bonds of chloramine. You need to add ten times the amount of CC to hit this point.

Try to reach the breakpoint every time you shock your pool. Not hitting the breakpoint can result in even more chloramines in your pool, and if the chloramine levels continue to rise unchecked, you may eventually have to partially or even fully replace your water to fix the issue.

If you want to learn more about the difference between free and combined chlorine, we wrote a full article about it here.

Types of Pool Shock

You generally can’t shock your pool using regular chlorine tablets, but you do have your choice of products when it comes to pumping up your chlorine levels.

1. Calcium Hypochlorite Shock

Also known as cal hypo, this chemical has been used to disinfect swimming pools and municipal water sources since 1928. It’s one of the most inexpensive and convenient ways to shock your pool.

• Most commercial versions contain between 65% and 75% chlorine.
• Calcium hypochlorite needs to be dissolved before you add it to your pool.
• It must be used after dusk.
• It will be roughly eight hours before you can safely swim again.
• It adds about 0.8 ppm of calcium to your water for every ppm of FC added, so use caution if your water source already has a high level of calcium.

Our Top Pick

Calcium Hypochlorite Pool Shock (Cal-Hypo Shock)

This fast-acting, quick-dissolving swimming pool shock from DryTec kills bacteria, controls algae, and destroys organic contaminants in pools. It comes in easy-to-use 1-pound bags.

Use the entire contents of the bag when opened. If any granules settle to the bottom of the pool use brush to disperse them. Add the right dosage of this product during evening hours while the filter pump is running.

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

2. Lithium Hypochlorite Shock

If your water has high calcium content, and you don’t mind paying a little extra, lithium hypochlorite is the way to go. It dissolves much more quickly than calcium hypochlorite, so you can add it directly to your pool without dissolving it beforehand.

• Commercial versions contain 35% chlorine.
• It must be used after dusk.
• It will be roughly eight hours before you can safely swim again.
• It can be toxic to aquatic life (making it a solid algaecide), so you must take care when disposing of recently treated water.

Note: You may have a difficult time finding lithium hypochlorite. Some pool chemical manufacturers have stopped producing it due to the rising cost of lithium, most of which is now used to make lithium batteries.

3. Dichlor Shock

The actual names of this swimming pool shock chlorine are sodium dichloro-s-triazinetrione or dichloroisocyanuric acid. (Try saying either of those five times fast.) Dichlor shock is much easier to say and even easier to use. Depending on the brand, you may be able to add it directly to your pool. Also, you can use this type of shock for saltwater pools.

• It typically contains between 50% and 60% chlorine.
• You can use it for both regular chlorine doses and shock treatments.
• You typically don’t have to dissolve it ahead of time.
• It adds 0.9 ppm of cyanuric acid for every ppm of additional FC.
• It must be used after dusk.
• It will be roughly eight hours before you can safely swim again.

Clorox Dichlor Pool Shock XtraBlue (1 Pound Bags), 12 Pack

This multifunctional pool shock from Clorox comes in a 12-pack. The algae-fighting granules create crystal clear water by killing bacteria and organic contaminants. It works well for smaller pools and saltwater pools. As a dichlor-based stabilized cholorine shock, it does contain cyanuric acid.

Buy Now on Amazon

If you click this link and make a purchase, we earn a commission at no additional cost to you.

4. Non-Chlorine Shock

If you’re looking to shock your pool and take a dip soon afterward, this is exactly what you need. Non-chlorine shock using potassium peroxymonosulfate is a fast, inexpensive pool shock alternative. This is the preferred shock for saltwater pools.

• You can add it directly to your pool water at any time.
• It will be roughly 15 minutes before you can safely swim again.
• Because it doesn’t rely on chlorine, it does not function as an algaecide.

Our Top Pick

In The Swim Chlorine-Free Oxidizing Pool Shock 24 x 1 Pound Bags

Powerful oxidizing agent that eliminates combined non-sanitizing chlorine (chloramines) and provides higher free chlorine levels. Helps eliminate algae growth as well as harmful bacteria. Ideal for use with chlorine or bromine sanitized applications, weekly maintenance, and will not affect other chemical levels

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

When to Shock Your Pool

The instructions on chlorine shocks say they need to be used after the sun has gone down. This is because the sun’s uv rays burn off unstabilized chlorine, which means the shock won’t be as effective. Shocking your pool at night makes sure the chemicals work the way they were meant to.

How Often Should You Shock Your Pool?

We recommend shocking your pool once a week, or at least once every other week to properly maintain sanitized water chemistry. The more often you use the pool, the more often you should reach for the swimming pool shock. In addition to your weekly or semi-weekly treatments, you may want to perform an extra pool shock under certain circumstances, such as after:

• heavy pool use (like a pool party)
• a severe rainstorm or damaging winds (especially if your pool collected debris)
• a major water level change
• a bowel-related pool accident

Think of extra shocks as insurance against wayward algae and other contaminants. It’s better to take out any bacteria before it has a chance to affect the quality of your water or make anyone sick.

How to Shock a Swimming Pool The Right Way

Superchlorinating your pool is shockingly (sorry, we couldn’t resist) easy once you get the hang of it. Also, this process works for any type of swimming pool including inground, above ground, and small inflatable or quick-set pools.

Important: Remember, if you’re using chlorinated pool shock, wait until the sun goes down before adding it.

Supplies For Shocking Your Pool

• Protective eyewear
• Chemical-resistant gloves
• Pants and a long-sleeved shirt (that you won’t mind messing up)
• Closed-toe shoes
• Water test strips or liquid testing kit
• Calcium Hypochlorite Pool Shock
• 5-gallon bucket (if you need to dissolve the pool shock before adding it to the water)
• Wooden stick (for stirring to dissolve)

Before you start, you’ll need to calculate your pool’s volume. If you don’t already know how much water your pool holds, you can use this pool calculator to figure it out.

Pool Volume Calculator Click on your pool shape to calculate the volume of water.

Rectangle

Round

Get Pool Volume

Get Pool Volume

1. Test The Pool Water

Do a quick round of pool water testing. The Free Chlorine level should be lower than the Total Chlorine level. This means your Combined Chlorine level is off and it’s time to shock your pool.

Also, check the pH and alkalinity levels. Make sure your pH level is between 7.4 – 7.6 and your alkalinity level is between 100 and 150 parts per million (ppm). This will balance the pool water chemistry so the shock treatment is more effective.

You can also check your calcium hardness level to make sure it’s in balance with the pH and Alkalinity. If your pool has a vinyl or fiberglass liner, the calcium hardness level should be between 175 parts per million (ppm) and 225 ppm. If you have a concrete or plaster pool, keep the level between 200 ppm and 275 ppm.

2. Pre-Dissolve Pool Shock

Carefully read the manufacturer’s instructions on your shock product. Most packages include charts or steps to help you calculate the amount of shock you need. If you need to calculate it yourself.

If you need to dissolve the shock first, fill your bucket roughly ¾ full with warm water. Add the shock to the bucket, and slowly stir until the chemical is as dissolved as possible. Work in one-pound increments.

3. Add Pool Shock To Water

If you do not need to dissolve your shock, count how many containers of shock you need. Add one bag at a time until you reach your calculated breakpoint.

At this point, make sure your pool pump and pool filter are running at full speed. This will help mix in the shock more effectively. Keep the system running for at least 8-12 hours after adding shock.

Slowly pour the shock while walking around your pool for more even distribution. (If your shock-water mix has solid particles at the bottom, dip the bucket into your pool water, carefully swish around to dissolve, and keep pouring.)

Wait to use your pool based on when you added the shock and the manufacturer’s recommendations. You don’t want to irritate your skin and eyes or bleach your swimsuit.

How to Shock a Saltwater Pool

Is it okay to shock a saltwater pool? A lot of pool owners think saltwater pools are different from traditional chlorine pools. But the salt in the water passes through a generator which turns it into chlorine. All saltwater pools are actually chlorine pools. The only benefit is that you don’t have to add the chlorine yourself. It’s being generated by your filter system.

This means you can shock your pool using the traditional shock methods outlined in this article. However, we recommend only using Dichlor or non-chlorine shock for saltwater pools.

You don’t always have to shock the pool this way. Most saltwater generators include a “super chlorinate” button that ramps up the production of the chlorine it produces helping you get to breakpoint chlorination, thereby “shocking” your pool.

And just like a traditional pool, we recommend doing this one a week or every two weeks depending on weather and usage. For heavy rain and/or high usage, shock your saltwater pool once a week.

Pool Shock Safety

Shocking your pool is a necessary part of good maintenance, but please remember those chemicals can be extremely dangerous if they’re mishandled. We’re not exaggerating the danger—improperly stored chlorine can literally explode.

• Never add shock through your pool skimmer, especially if you have an automatic chlorinator. When the shock treatment mixes with the chlorine, it causes a dangerous gas, which can lead to your chlorinator exploding! We’ve seen it happen multiple times.
• Always wear protective gear—especially goggles and chemical-resistant gloves—when handling and dissolving chlorine. Pool shock, especially calcium hypochlorite, can sometimes release small amounts of chlorine gas. Wearing protective gear can help prevent eye and skin irritation.
• Do your best to avoid directly breathing from the containers. Exposure to chlorine gas can cause throat and lung irritation. You probably don’t need a dust mask, just try not to breathe too close to the container. If it makes you feel safer, though, you can use a chemical mask.
• Never, ever mix types of pool shock. We don’t want you to become a home science experiment gone wrong. Mixing liquid chlorine or even dry chlorine granules can cause a volatile reaction. Add each chemical to your pool separately.
• Do not add shock directly to the pool water unless instructed to do so. If the package says dissolve before adding, make sure to do just that.
• Only open one container at a time. If you need to use more than one container of shock, make sure you completely empty out each container before moving on to the next one.

Frequently Asked Questions About Shocking Your Pool

Looking for more help with shocking your pool? Here are some common questions and answers.

Are chlorine and shock the same thing?

No. There are versions of shock that have chlorine, like Calcium Hypochlorite. But some pool shock treatments have no chlorine. However, you can use a high dose of liquid or granular chlorine to shock your pool.

Can I shock my pool without the pump running?

We recommend running your pump and filter when you’re actively shocking your pool and for at least 8-12 hours after. If you don’t run your pump and circulate the water, you run the risk of bleaching your pool walls and floor if you’re using chlorine shock.

Can I swim 12 hours after shocking the pool?

It’s usually safe to swim after letting the shock circulate in the water for at least 8 hours. However, we recommend testing the water’s chlorine level before swimming. A high chlorine reading may be uncomfortable and dangerous to swimmers.

Does pool shock work in cold water?

Yes, but no matter what the temperature of your pool water, we recommend dissolving shock in a bucket of warm water before adding it. This will help dissolve the shock so it doesn’t sit on the bottom of your pool and cause bleaching. Plus, it helps it to mix into the water better and faster.

Need More Pool Maintenance Help?

• Download our free Pool Care Cheat Sheet. It’s a free, easy-to-use guide to help you keep track of taking care of your pool.
• Subscribe to our Swim University YouTube Channel. We publish free video tutorials throughout the pool season.
• Check out our Pool Care Course. You’ll get 30+ step-by-step videos and a step-by-step downloadable guide with everything you need to know about pool maintenance.

Happy Swimming!

The post How to Shock a Pool The Right Way appeared first on Swim University®.

But having too little or too much CYA in your pool can inhibit your chlorine’s effectiveness and even damage your pool equipment. That’s why maintaining the right cyanuric acid levels is so important to help your chlorine actively kill bacteria, contaminants, and algae.

Here’s everything you need to know about how cyanuric acid interacts with chlorine and how to maintain the right CYA levels in your pool.

You can watch the quick video tutorial below. Or keep reading for the step-by-step guide on how to adjust your CYA levels.

How Does Cyanuric Acid Work in a Pool?

Cyanuric acid, or chlorine stabilizer, reduces the amount of chlorine that’s destroyed by the sun’s UV rays. CYA helps your chlorine last longer, which means your chlorine can sanitize your pool water longer.

If you have an outdoor pool without CYA or stabilizer, your chlorine will dissipate in a few hours, leaving your pool unprotected and unsanitized. In fact, it only takes 17 minutes of exposure to UV rays to destroy half of your chlorine. Imagine a chlorine tablet losing half of its chlorine in such a short period of time!

Pools with very low or no cyanuric acid experience “chlorine demand,” or the inability to maintain chlorine levels. No matter how much chlorine you add, the levels drop quickly. Chlorine without CYA, also known as unstabilized chlorine, is destroyed by UV rays very quickly. Adding stabilizer helps your chlorine last 3-5 times longer.

But not every pool owner needs to worry about CYA levels. Because cyanuric acid protects chlorine from the sun, it’s really only required for outdoor pools (or indoor pools with some ultraviolet light exposure). CYA stays in a swimming pool for a long time, even after the water evaporates. So always check your cyanuric acid levels before adding more chlorine stabilizer to your water.

What Are the Right CYA Levels?

The ideal range for cyanuric acid is between 30 and 50 ppm. Too much CYA and your chlorine’s effectiveness decreases. Too little CYA and your chlorine will break down under the sun’s UV rays.

But it’s the ratio of CYA to chlorine that’s most crucial. Your free chlorine levels should be 7.5 percent of your cyanuric acid levels. If your pool has CYA levels at 40 ppm, you’ll need to keep your free chlorine levels at 3 ppm to effectively sanitize your water. And general, your free chlorine levels should be between 1 ppm and 3 ppm.

However, if you’re a saltwater pool owner, you’ll need to maintain higher CYA levels. The sun’s UV rays are doubly harmful to saltwater pools, impacting both the salt itself and the chlorine generated from that salt. Saltwater pool manufacturers recommend keeping your cyanuric acid levels between 60 and 80 ppm. 

Remember, more cyanuric acid does not mean more protection from the sun. If your CYA levels are high, you may experience algae growth or cloudy pool water. That’s because your chlorine’s effectiveness is reduced. If your CYA levels are 100 ppm or higher, you may not even be able to get an accurate reading on a test strip.

If your cyanuric acid levels are off the charts, take a water sample into your local pool supply store or use a test kit that measures CYA levels up to 300 ppm.

By the way: if you’re tired of constantly troubleshooting your pool and want help never dealing with water chemistry problems again, check out our pool maintenance video course!

Frustrated by adding chemicals and trying to keep your pool clear all the time?

We cut out all the confusion of pool maintenance in this easy-to-read illustrated ebook and video course. It'll help you save $100 right away on pool care!

Click Here to Learn More

What Causes High Cyanuric Acid Levels?

If you’re adding chlorine to your water, there’s a good chance you’re adding cyanuric acid along with it. Many chlorine products, like trichlor or dichlor granules or tablets, are known as stabilized chlorine products. This means they already come with CYA. Every time you add chlorine to your pool, you’re adding cyanuric acid.

On the other hand, unstabilized chlorine, like liquid chlorine, doesn’t include CYA. You can learn more about the difference between stabilized and unstabilized chlorine here.

If you need to add CYA to your pool, you can buy it as a separate product. It’s usually called pool stabilizer or pool conditioner. Here is the stabilizer we recommend:

Our Top Pick

Cyanuric Acid (Chlorine Stabilizer) for Pools

Keep your chlorine from being burned off too quickly by the sun's UV rays. CYA will help you keep a better chlorine reading in your pool.

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

Just be careful how much extra cyanuric acid you add to your water. It’s very hard to lower your CYA levels if they’re too high. And cyanuric acid does not evaporate or break down like chlorine, so it will linger in your pool water. It can even hang around in your filtration system and pool plaster.

How to Lower Cyanuric Acid in Your Pool

The only effective way to lower your CYA is to partially drain your pool and refill it with fresh water. If you think your cyanuric acid is too high, the first step is to stop adding more CYA or stabilized chlorine to your pool before diluting your water.

1. Test Your Pool Water

Test your swimming pool water to see if your CYA levels are between 30 and 50 ppm. If your cyanuric acid levels are 100 ppm or above, you may need to run multiple tests as you bring your CYA levels down. You can also take a water sample to your local pool supply store or purchase a test kit that will measure your cyanuric acid up to 300 ppm.

Our Top Pick

Complete Liquid Test Kit for Pools and Hot Tubs

A simple but effective liquid test kit for chlorine pools and hot tubs.

Buy Now On Amazon

If you click this link and make a purchase, we earn a commission at no additional cost to you.

2. Stop Using Stabilized Chlorine

Check to see if you’re using stabilized chlorine, which already contains small amounts of cyanuric acid. If you see these chemicals listed on the label, your chlorine contains CYA:

• potassium dichloroisocyanurate
• sodium dichloroisocyanurate
• trichloroisocyanurate

In the short term, switch to chlorine without cyanuric acid to prevent your high CYA levels from getting worse.

3. Dilute Your Pool Water

If the amount of cyanuric acid in your water is very high, you must dilute your pool water. Partially drain some of your pool water by using a manual vacuum on your filter’s waste setting. Then refill your pool with fresh water.

As a general rule of thumb, if your CYA levels are 10% too high, you’ll want to remove and replace about 10% of your pool water. But be aware that cyanuric acid can hang around in your filtration system. So if you have extremely high levels of CYA, you may also want to backwash or change your filter.

4. Circulate and Retest Your Cyanuric Acid Levels

Run your pump for a few hours to circulate the freshwater. Then retest your cyanuric acid levels again. If they’re still too high, repeat the process and dilute more of your pool water.

Do Cyanuric Acid Reducers Work?

Cyanuric acid reducers have mixed results, and the only guaranteed way to reduce your CYA levels is by diluting your water.

Cyanuric acid reducers are biologically based, so they work slowly. It can take a week or more to reduce your CYA levels, and many customers have reported seeing no results.

And CYA reducers are not cheap. You could partially drain and refill your pool for roughly the same price, depending on the water utility costs in your area. But if you can’t dilute your pool water (say because of drought conditions or municipality restrictions), it might be worth trying a cyanuric acid reducer.

How to Raise Cyanuric Acid in Your Pool

If you do need to raise your cyanuric acid levels, you’ll likely only need to add it once or twice per year (usually at the beginning of the season). But be careful about adding too much CYA. Remember that cyanuric acid does not break down in the water and can stay in your pool for a long time. And stabilized chlorine (like dichlor or trichlor) already comes with CYA, so you’ll likely be adding it to your pool water throughout the season.

Because CYA is an acid, you’ll need to handle it carefully. It can damage your filter and your pool, especially if you have a vinyl liner. Here is the safe way to add stabilizer to your pool.

You’ll need the following supplies:

• Cyanuric acid (a.k.a. conditioner or stabilizer)
• A 5-gallon bucket
• Safety goggles
• Acid-resistant gloves
• Protective clothing (i.e. long sleeves, closed-toe shoes)
• Warm water

To add cyanuric acid to your pool:

1. Fill the bucket at least halfway with warm water.
2. Put on your goggles and gloves.
3. Add a dose of stabilizer to the bucket. Check the product instructions for the right dose based on your pool size. As a general rule, add 13 ounces of cyanuric acid to gain 10 ppm of CYA in a 10,000-gallon pool. Remember, your CYA should be between 30 and 50 ppm.
4. Pour the contents of the bucket directly into your skimmer.
5. Run your pool pump for at least a few hours after. Letting the pump helps mix the solution into your pool.

Note: Some packages of cyanuric acid say to add the chemical directly to the skimmer without first combining it with water. Always read and follow the manufacturer’s instructions.

How to Maintain the Right CYA Levels

Regular water testing will help you maintain the right amount of cyanuric acid in your water. This is especially important if you’re using stabilized chlorine or you tend to have problems with high CYA.

Check your pool chemistry once a week with test strips that measure CYA or cyanuric acid. Remember, your free chlorine levels should be about 7.5 percent of your CYA levels. That means if your free chlorine is at 3 ppm, your levels of cyanuric acid should be around 40 ppm.

Also, be sure to test your water chemistry after a rainstorm. Rainwater will dilute your water and lower your CYA levels.

Our Top Pick

Complete Liquid Test Kit for Pools and Hot Tubs

A simple but effective liquid test kit for chlorine pools and hot tubs.

Buy Now On Amazon

If you click this link and make a purchase, we earn a commission at no additional cost to you.

Frequently Asked Questions about Cyanuric Acid

Looking for more help with using CYA in your pool? Here are some common questions and answers.

Is Cyanuric Acid Harmful?

While cyanuric acid is technically an acid, it’s very different from other acids (like muriatic acid). Cyanuric acid dissolves in water and does not significantly affect your pH, alkalinity, or calcium hardness levels.

However, like other pool chemicals, cyanuric acid must be handled with caution. CYA can cause severe burns if it comes in contact with your skin or eyes. And its fumes can burn your nose or lungs if inhaled. Always wear acid-resistant rubber gloves, eye protection, long sleeve clothing, and handle CYA in a well-ventilated area.

Do I Need Cyanuric Acid in an Indoor Pool?

Cyanuric acid helps prevent chlorine from breaking down in the sun’s UV rays. If you have an indoor pool that is not exposed to sunlight, you do not need to use CYA.

Cyanuric acid does not evaporate like other chemicals and too much CYA in the water can inhibit your chlorine’s ability as a sanitizer. In fact, the CDC has limited CYA levels to 15 ppm in public pools.

But if you have an indoor pool and it receives some UV ray exposure, and your chlorine levels keep dropping, you may want to consider maintaining a low level of CYA.

Is There Another Name for Cyanuric Acid?

Cyanuric acid is called CYA, pool stabilizer, or conditioner. It’s sold separately as conditioner and stabilizer or it’s included in chlorine products like trichlor or dichlor.

Does Pool Shock Contain Cyanuric Acid?

Some pool shock, like dichlor shock, contains cyanuric acid. But we recommend using unstabilized chlorine shock without CYA. This ensures you’re not adding unnecessary CYA to your water each time you shock your pool. We recommend using calcium hypochlorite shock, also known as cal-hypo shock.

Our Top Pick

In The Swim Chlorine-Free Oxidizing Pool Shock 24 x 1 Pound Bags

Powerful oxidizing agent that eliminates combined non-sanitizing chlorine (chloramines) and provides higher free chlorine levels. Helps eliminate algae growth as well as harmful bacteria. Ideal for use with chlorine or bromine sanitized applications, weekly maintenance, and will not affect other chemical levels

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

Is Cyanuric Acid the Same as Baking Soda?

No, cyanuric acid and baking soda work in very different ways in your pool. Baking soda raises the total alkalinity in your pool. But baking soda does not protect or stabilize your chlorine, like CYA.

What Raises Cyanuric Acid in a Pool?

You can raise your cyanuric acid levels by adding a pool conditioner or stabilizer. If you do need to add CYA to your pool, here’s the stabilizer we recommend:

Our Top Pick

Cyanuric Acid (Chlorine Stabilizer) for Pools

Keep your chlorine from being burned off too quickly by the sun's UV rays. CYA will help you keep a better chlorine reading in your pool.

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

How Do High Cyanuric Acid Levels Affect a Pool?

When cyanuric acid levels get too high, it can hinder the effectiveness of your chlorine. If your chlorine test shows very little or no chlorine right after you’ve added it to the pool, your CYA may be too high. The only way to reduce CYA levels is to dilute your water by draining and refilling your pool.

Need More Pool Maintenance Help?

• Download our free Pool Care Cheat Sheet. It’s a free, easy-to-use guide to help you keep track of taking care of your pool.
• Subscribe to our Swim University YouTube Channel. We publish free video tutorials throughout the pool season.
• Check out our Pool Care Course. You’ll get 30+ step-by-step videos and a step-by-step downloadable guide with everything you need to know about pool maintenance.

The post Cyanuric Acid: Why Your Pool Needs It and How To Balance It appeared first on Swim University®.

What is an Automatic Pool Chlorinator?

Also known as an automatic chlorine feeder, an automatic chlorinator automatically dispenses chlorine into your pool. So instead of manually adding chlorine to your pool water or adding chlorine tablets to your floating dispenser or pool skimmer, you add chlorine tablets directly to your chlorinator.

The chlorine dissolves in the chlorinator and disperses into your water at a steady rate. That means consistent chlorine levels flow into your pool.

With a little upfront cost and installation, a chlorinator eliminates the need to constantly measure and add chlorine to your water or refill your floating chlorine dispenser.

Here’s a step-by-step guide on how automatic pool chlorinators work, the different types, and why they’re a great investment for most swimming pool owners. And if you’re in the market for one right now, here’s the one we recommend:

Our Top Pick

Hayward Automatic Pool Chlorinator (Inline)

This automatic chlorinator is perfect for the pool owner who hates fussing with chlorine tablets. With its dial control valve, you can easily adjust the chlorine level depending on your pool's size.

Buy Now On Amazon

If you click this link and make a purchase, we earn a commission at no additional cost to you.

FYI: We’re a small team of pool industry experts and researchers that care about recommending quality, reliable pool products. If you choose to click a link and buy any of the products we recommend, we earn a commission at no additional cost to you.

How Does a Chlorinator Work?

An automatic pool chlorinator plugs directly into your pump and filter system, where it disperses a steady, measured amount of chlorine into the water that’s returning to your pool. As water passes through it, it slowly dissolves the chlorine tablet inside. It then dispenses that chlorine into your water based on your settings.

Simply add chlorine tablets to your chlorinator and choose your chlorine level (between 1 and 3 ppm) based on the volume of your pool. Then let the chlorinator do the work of adding chlorine consistently to your water!

With a pool chlorinator, you won’t need to add chlorine to a pool chlorinator as often as you’d need to add granular chlorine to your pool water. And you won’t need to worry about floating chlorine dispensers getting stuck behind ladders or adding chlorine tablets to your skimmer that can stain your pool’s vinyl liner.

But it’s not completely hands-free at the beginning. When you’re first using your pool chlorinator, be sure to regularly test your chlorine levels until you get a feel for the setting that works best based on your pool. And because pool chlorinators are part of your pool filter and pump system, they will not dissolve your chlorine tablets if your pool pump is off. So be sure to monitor your chlorine levels if you have a timer for your pool pump.

Wondering if a floating chlorine dispenser or putting chlorine tablets in your skimmer is a better option? Here’s a quick video tutorial on the difference between using floating dispensers, adding chlorine pucks in your skimmer, and installing an automatic pool chlorinator.

What are the Different Types of Automatic Pool Chlorinators?

There are two types of pool chlorinators: inline and off-line pool chlorinators. They both function the same and cost the same (usually under $100). But they are installed differently, and they won’t work with every type of pool set up. An inline pool chlorinator is installed directly into the plumbing of your pump and filter system. An off-line pool chlorinator, on the other hand, is connected with a tube installed on the side of the filter system.

You’ll need to select the automatic pool chlorinator that will fit into your filtration system. Some of these chlorinators can be used in both inground and above ground pools, while other models are specific to one or the other.

Inline Pool Chlorinator

An inline chlorinator is connected directly to your filtration system, after the filter or heater, and before the filtered water is returned to the pool. Since it’s chlorinating the water after it’s passed through the filter and heater, it helps protect pool equipment from corrosion.

Inline chlorinators are plumbed into PVC piping. It’s easiest to hard plumb a chlorinator during pool construction or renovation, but it’s possible to cut the PVC pipe and install a chlorinator after the fact.

An inline chlorinator is a sturdier option with fewer parts than an off-line chlorinator. But you might not have enough space to install an inline chlorinator into your pump and filter set up.

Off-line Pool Chlorinator

If you don’t have the space to add an inline chlorinator at the end of your filtration system, you can install an off-line pool chlorinator. An off-line chlorinator is connected through a separate line that bypasses the rest of the filter equipment.

It’s an option for pool owners that still want an automatic pool chlorinator but don’t have enough room to install an inline model. While you won’t need to cut any piping to install, you will still need to cut small holes into your PVC plumbing.

You can only use an off-line chlorinator if you have “hard” PVC piping. If you have soft flexible hosing, which is common in above ground pool plumbing, you won’t be able to use an off-line chlorinator.

Are you still confused about your pool anatomy and your filtration system? Check out our pool maintenance video course for a step-by-step tutorial so you can finally understand the ins and outs of your pool.

Frustrated by adding chemicals and trying to keep your pool clear all the time?

We cut out all the confusion of pool maintenance in this easy-to-read illustrated ebook and video course. It'll help you save $100 right away on pool care!

Click Here to Learn More

What is the Best Automatic Pool Chlorinator?

When shopping for a pool chlorinator, first look for the model that’s compatible with your type of filter system and that can handle your pool’s volume. Some chlorinators are made to sanitize 10,000-gallon pools, and others will sanitize up to 40,000 gallons. If you get a chlorinator that’s too small for your pool, the water won’t be completely sanitized, so be sure you choose an appropriate size.

Here’s the pool chlorinator we recommend:

Our Top Pick

Hayward Automatic Pool Chlorinator (Inline)

This automatic chlorinator is perfect for the pool owner who hates fussing with chlorine tablets. With its dial control valve, you can easily adjust the chlorine level depending on your pool's size.

Buy Now On Amazon

If you click this link and make a purchase, we earn a commission at no additional cost to you.

Whenever buying pool equipment, such as a pool chlorinator, it’s important to look for well-established brand names like Hayward. They make it easier to find replacement parts in the future and they usually come with a manufacturer’s warranty.

What Kind of Chlorine Is Used in a Pool Chlorinator?

Pool chlorinators work best with slow-dissolve trichlor chlorine tablets or pucks. These tablets last longer than liquid chlorine or granules, giving you more time between pool chemical additions. But more importantly, pool chlorinators use water pressure to dissolve chlorine pucks at a steady rate and granular chlorine will dissolve too quickly.

Chlorine pucks or tablets will only dissolve in your chlorinator when your pool pump is running. If your pump is on a timer and turns, your chlorine will not dissolve and therefore it won’t disperse into your pool.

When you first start using your pool chlorinator, check your chlorine tablets’ dissolve rate and test your chlorine levels at least once a week to make sure there’s enough chlorine getting into your pool water.

Our Top Pick

3-Inch Stabilized Chlorine Tablets

Stock up and save money on chlorine tablets for the season by getting the standard 3-inch stabilized chlorine pucks.

Buy Now On Amazon

If you click this link and make a purchase, we earn a commission at no additional cost to you.

IMPORTANT: Do NOT mix two or more different types or brands of chlorine in your chlorinator at the same time. You could risk an explosion. Stick to one type of chlorine, like trichlor tablets, and the same brand, if possible.

How to Set Your Chlorination Rate

Just like any other chemical, the amount of chlorine you add to your pool will depend on your pool’s volume. You’ll need to know this before you can set the chlorinator’s dispensation rate.

If you don’t already know your pool’s volume, you can use a pool calculator to figure it out. Your pool’s water volume is calculated using your pool’s surface area times your pool’s average depth.

Pool Volume Calculator Click on your pool shape to calculate the volume of water.

Rectangle

Round

Get Pool Volume

Get Pool Volume

To add chlorine tablets to your chlorinator, be sure to turn the power to your pool pump off first. Then use the chlorinator air vent to release air pressure or remove the chlorinator cap slowly to avoid inhaling chlorine fumes (and wear protective gear, like goggles and a mask). Add the chlorine tablets and then reset the control valve dial to your desired level and turn the pump back on.

You can add as many chlorine tablets as you want. How quickly they dissolve depends on your chlorinator setting, your chlorine demand, and your water flow rate.

When first setting your chlorination rate, start on a lower setting for the first two or three days. Then test your water and increase your chlorination until your free chlorine levels reach between 1 and 3 ppm. Make sure your water chemistry is balanced, including your pH and Alkalinity levels. If you need help balancing your water chemistry, be sure to check out our guide to Basic Pool Chemistry 101.

Is A Pool Chlorinator Worth It?

We definitely think a chlorinator is a worthwhile investment:

• It automatically and evenly dispenses chlorine (even when you’re out of town)
• You can control the rate that chlorine flows into your pool
• You can avoid chlorine tablets in your pool or skimmer (and the vinyl liner stains they can cause

On the downside, it may be difficult to initially install. And with any piece of equipment, it requires maintenance over time. It also requires the same type of chlorine tablets every time you use it (mixing different types of chlorine in your chlorinator is dangerous).

But regardless of the upfront cost and hassle of installation, a chlorinator is a great investment for a hands-free (and worry-free) way to keep your pool chlorinated and sanitized. Again, here’s the one we recommend:

Our Top Pick

Hayward Automatic Pool Chlorinator (Inline)

This automatic chlorinator is perfect for the pool owner who hates fussing with chlorine tablets. With its dial control valve, you can easily adjust the chlorine level depending on your pool's size.

Buy Now On Amazon

If you click this link and make a purchase, we earn a commission at no additional cost to you.

Frequently Asked Questions About Automatic Pool Chlorinators

Looking for more help understanding more about chlorinators? Here are some common questions and answers.

Are pool chlorinators safe?

When used properly, chlorinators are safe to use. But you must take all safety precautions when handling chlorine or chlorine feeders. Turn off your pool pump before opening your chlorinator and wear proper protection, like goggles, gloves, and a mask. Avoid inhaling chlorine fumes when removing the cap or by using your chlorinator’s air vent to release air pressure. Always follow the manufacturer’s instructions (which may differ from these) and never, EVER mix the types of chlorine you use.

Is there an automatic chemical feeder for bromine?

If you have a swimming pool or hot tub that uses bromine, you can use an automatic chemical feeder like a chlorinator (it’s sometimes marketed as a brominator). The only difference is that instead of chlorine tablets, you’ll add bromine tablets to the feeder. If you switch from chlorine tablets to bromine tablets or vice versa, you will need to purchase an entirely new one. Remember, mixing different chemicals like chlorine and bromine can cause a dangerous chemical reaction or explosion.

What is the difference between an Automatic Pool Chlorinator and a Salt Water Chlorinator?

A chlorine generator, also known as a saltwater chlorinator or saltwater generator, creates chlorine from salt and disperses that chlorine into your saltwater pool. Automatic pool chlorinators, also known as automatic chlorine feeders, dispense chlorine from chlorine tablets that are added to the chlorinator.

Do chlorine pools have a chlorinator?

Not all chlorine pools have one already installed. You will either have to manually add chlorine granules or powder directly to your water or add a chlorine tablet to a chlorine floater or directly into your skimmer basket. But pool chlorinators are relatively affordable (usually $100 or less) and make pool maintenance much easier once installed.

Need More Pool Maintenance Help?

• Download our free Pool Care Cheat Sheet. It’s a free, easy-to-use guide to help you keep track of taking care of your pool.
• Subscribe to our Swim University YouTube Channel. We publish free video tutorials throughout the pool season.
• Check out our Pool Care Course. You’ll get 30+ step-by-step videos and a step-by-step downloadable guide with everything you need to know about pool maintenance.

The post Automatic Pool Chlorinators: How Do They Work and Are They Worth It? appeared first on Swim University®.

What Is Chlorine Pool Stabilizer?

Pool stabilizer is also known as pool conditioner, chlorine pool stabilizer, chlorine stabilizer, or Cyanuric Acid. And you can buy this chemical additive as either liquid or granular (powder). It’s also included in chlorine tablets or sticks (called trichlor) or shock (called dichlor). When they’re mixed together in shock or tablets, the resulting product is called stabilized chlorine.

Typically, pool owners won’t need to add any extra stabilizer separately if you’re using one of the combination products. In fact, if you add too much, you might develop a problem called “creep,” which describes the stabilizer chemical’s tendency to build up to problematic levels over time. Too much of any chemical in your pool is never a good thing.

To determine how much chlorine stabilizer is in your water, you need to check your CYA level. You can check using either test strips, a liquid test kit, or taking a water sample to your local pool supply store. Just make sure if you’re testing it yourself that you buy a test kit or strips that can check for CYA or Cyanuric Acid levels.

If your pool stabilizer levels creep too high, it can reduce the effectiveness of your sanitizer, or in other words, do the exact opposite of what it’s meant to do.

The only way to lower stabilizer levels in your pool is to remove some of the water and add clean water. Once you do that, you’ll have to balance all your chemicals again.

Real quick, are you tired of not knowing what to do when it comes to pool maintenance? We have a video course designed by a professional pool care expert that’ll show you how to keep your pool clean and clear all the time without all the stress and confusion.

You can finally take control of your own pool care without spending hours reading through manuals or searching online for answers. Click here now and sign up for our Pool Care Video Course today!

Frustrated by adding chemicals and trying to keep your pool clear all the time?

We cut out all the confusion of pool maintenance in this easy-to-read illustrated ebook and video course. It'll help you save $100 right away on pool care!

Click Here to Learn More

What is the Stabilizer in a Pool?

In the simplest of terms, a pool conditioner or stabilizer helps your chlorine stay in the water longer. In other words, it prevents drastic chlorine loss. More specifically, it binds to chlorite ions (your free chlorine), making them impervious to the sun’s rays.

Without it, ultraviolet rays would break apart the chlorite ions, allowing the chlorine to evaporate into the air. It literally stabilizes the ion. Your free chlorine will then be available for sanitizing three to five times longer than it would be without using a stabilizer.

But that longer lifespan comes with a bit of a catch. When stabilizer forms a bond with chlorine, its sanitizing ability, which goes by the fancy name Oxidation Reduction Potenial (ORP), is somewhat hindered. In other words, it takes stabilized chlorine longer to kill bacteria than it takes chlorine without stabilizer.

Our Top Pick

Cyanuric Acid (Chlorine Stabilizer) for Pools

Keep your chlorine from being burned off too quickly by the sun's UV rays. CYA will help you keep a better chlorine reading in your pool.

Buy Now On Amazon Buy on InTheSwim.com

If you click this link and make a purchase, we earn a commission at no additional cost to you.

In fact, if you also have a hot tub, this is the reason you absolutely should not add a stabilizer to your spa. The bacteria that cause folliculitis, Pseudomonas aeruginosa, takes 100 times longer to be eliminated from a spa with stabilized chlorine, leaving you and your hot tub guests vulnerable to infection.

The good news is as long as you maintain proper free chlorine levels, the stabilizer is incredibly helpful in extending the life of your chlorine, helping maintain proper pool chemistry, and saving you money.

How Much Pool Stabilizer Should You Use?

Before you start adding chemicals to your pool, you need to know how much CYA is already in your water. CYA can get into your water just by adding chlorine tablets or some types of shock.

And before you test, you should know exactly how many gallons of water your pool holds. We have this handy built-in calculator you can use to find out:

Pool Volume Calculator Click on your pool shape to calculate the volume of water.

Rectangle

Round

Get Pool Volume

Get Pool Volume

You’ll find wide variations among recommendations for the optimal levels of stabilizer in your pool, from a few parts per million (ppm) to 100 ppm, and everything in between.

We recommend nothing higher than 50 ppm. At that concentration, the difference in chlorine effectiveness between pools with stabilizer and without becomes noticeable. You may also see more algae growth at levels above 50 ppm due to the negative effect on your free chlorine.

Just to reassure you even further, stabilizer levels above 50 ppm do not provide any significant increase in UV protection for chlorine, but they do increase the risk of bacteria and algae growth.

With your pool stabilizer at 50 ppm or lower, you’ll still want to monitor your available chlorine through regular, frequent water testing to ensure your pool is properly sanitized.

To maintain a healthy balance of free chlorine and stabilizer, aim to keep your sanitizer levels at 7.5 percent of your stabilizer level. This means if your pool conditioner is 50 ppm, you’ll want the free chlorine level to be around 3 ppm, the ideal level in any case.

Warning: One exception to the recommended levels of chlorine stabilizer must be made in the event of cryptosporidium contamination. Cryptosporidium, also called crypto, is a parasite sometimes introduced to pools through fecal contamination, and it’s highly resistant to chlorine. You may sometimes hear about municipal pools or splash pads being closed “due to crypto contamination,” which requires serious intervention to eliminate.

Due to the parasite’s ability to survive under normal chlorine levels, if you encounter this type of contamination in your pool, you must lower your pool stabilizer levels to a maximum of 15 ppm before hyperchlorinating. You’ll also need to backwash or replace your filter and balance the water before letting anyone back into your pool.

When Should You Add Chlorine Stabilizer To Your Pool?

Does adding chemicals to your pool once a year sound too good to be true? Well, it is—except in the case of pool stabilizer. Because the chemical doesn’t get used up while working, nor does it gas off like other pool additives, it simply remains in your water.

The levels typically won’t ever decrease unless you have significant splashout or evaporation, requiring you to add water. Dilution (whether from rain or top-off) will also lower stabilizer concentration in your pool.

When you use stabilized chlorine in your pool every week, you’re adding a touch of stabilizer every time you add chlorine. You really won’t need more than that throughout the year to keep pool stabilizer at the appropriate concentration.

However, it’s because of this that pool stabilizer levels can creep up over time, particularly if you don’t need to top off your pool very often. Buy quality pool chemistry test strips, and you’ll be able to keep an eye on your stabilizer level when you test your water each week.

If you notice your stabilizer level creeping up, check your water level. Topping off your pool may be enough to knock it back down a bit.

You may also switch to non-stabilized chlorine, which comes in liquid and granules. Just be sure to monitor your water chemistry, so you can switch back or add stabilizer as needed.

How to Add Pool Stabilizer

Some pool chemical instructions tell you to add them at the filter, while others may be poured straight into the pool water. When it comes to pool stabilizer, you don’t want to do either of those, even if the instructions say it’s okay.

Remember that pool stabilizer is an acid. The chemical dissolves very slowly. In fact, that the acidity can damage your pool surfaces or skimmer if left to sit there and dissolve in its own time.

We recommend buying a five-gallon bucket, filling it with water, then dissolving the stabilizer in that water. This way, whether it takes ten minutes or an hour to dissolve, you won’t be damaging expensive pool surfaces or delicate circulation parts by leaving an undiluted acid lying around on them.

Note: Never add chemicals to your skimmer and through your pool filter. This can be very dangerous and could damage your pool filter system.

Do You Really Need a Chlorine Pool Stabilizer?

You already know you should definitely never add conditioner to a hot tub, and you could probably guess that indoor swimming pools won’t benefit from pool stabilizers because they aren’t typically directly exposed to UV rays.

But is there any compelling reason against using a pool stabilizer in outdoor pools?

Nope. If you own an outdoor chlorine or saltwater-chlorinated inground or above ground pool, proper stabilizer use will save you time and money on chlorine.

Sure, too much stabilizer can cause problems. Just be sure to keep an eye on it every week along with chlorine concentrations to ensure proper pool chemistry.

You’ll rest easy knowing your pool is safely swimmable for your whole family—without having to add extra chlorine for every hour of sunshine.

Happy Swimming!

The post How to Protect Your Chlorine Level with Pool Stabilizer appeared first on Swim University®.