Check out the video below for how to lower your alkalinity with muriatic acid or keep reading for our complete guide.

What is Total Alkalinity?

Alkalinity acts as a buffer to your pool water’s pH, helping keep your pH levels from fluctuating drastically. So balancing your total alkalinity is important in order to maintain consistent pH levels.

Your total alkalinity should be between 100 and 150 parts per million (ppm). And your pH should be between 7.4 and 7.6. Anything much higher or lower will disrupt your water chemistry, affect your pool’s ability to sanitize, and can damage your pool equipment in the long run.

How Do Alkalinity and pH Affect Each Other?

If your total alkalinity is too low, there’s not enough of this helpful buffering chemical in the water to help stabilize your pH. When your total alkalinity is too high, the elevated alkalinity may cause your pH level to rise along with it. And that can reduce the effectiveness of the chlorine in your water.

So if your total alkalinity is in the normal range (100 to 150 ppm), your alkalinity will help stabilize your pH. And stabilized pH helps your chlorine do its job to sanitize your swimming pool.

By the way, we know pool water chemistry can be extremely confusing. So if you want a step-by-step guide on how to keep your water balanced, check out our Pool Care Video Course.

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What Causes High Total Alkalinity?

Unfortunately many of the pool chemicals you add to your water can impact your total alkalinity. Similarly, low levels of chlorine and a high bather load can bring your pH and alkalinity levels up.

Cyanuric Acid

The most common chemical that raises total alkalinity is cyanuric acid (a.k.a. CYA or chlorine stabilizer). CYA is used to stabilize your chlorine and prevent it from evaporating due to the sun’s UV rays. And it also acts as a buffer to the acidity caused by chlorine.

For example, stabilized trichlor chlorine has a pH of around 3. So when you use trichlor chlorine to sanitize your water, you are making it more acidic. But because it’s stabilized, it contains cyanuric acid. And that buffers the acidity in your pool water. Buffered acidity can raise the alkalinity.

That’s why it’s so important to routinely test your pool water chemistry with test strips or a liquid test kit to ensure all of your levels remain properly balanced.

Low Sanitizer Levels

The other thing that can affect your alkalinity and pH is a high bather load in water with low chlorine. So if you have low chlorine levels and lots of swimmers in the water, they can leave behind contaminants that disrupt pH. And disrupted pH can disrupt the total alkalinity.

Pool Shock

You may also have issues with high alkalinity levels when you shock your pool. While it’s important to shock your pool on a regular basis, chlorine-based pool shocks are highly alkaline and will raise pH and therefore alkalinity. So you may notice higher pH and total alkalinity after shocking your water.

What Happens if Your Pool Alkalinity is Too High?

Since your alkalinity impacts your pH, and your pH impacts almost everything in your water, high alkalinity can cause a range of issues.

Causes High pH

If the alkalinity is too high, chances are your pH is too high. And if you have high pH, you may experience cloudy water and scaling. Plus scaling inside the pipes will restrict water flow, which puts a strain on your circulation and filtration system.

Reduces Chlorine Effectiveness

Total alkalinity levels affect your pH, which affects chlorine. And as a result, your pool’s chlorine will become less effective at sanitizing the water.

May Irritate Skin and Eyes

If the alkalinity and pH levels are off, swimmers can experience itchy skin and burning eyes. And it may also shorten the life of your bathing suit fabric and goggles.

Leads to Scale Build Up

Because high alkalinity disrupts the pH balance, it can lead to calcium buildup. And with high calcium, you may see scaling throughout your pool. You may also have visible calcium deposits collecting on the pool surface or calcium hardness buildup that you can’t see inside your pool equipment.

Creates Cloudy Water

High alkalinity can lead to calcium buildup. And high calcium levels in the water create cloudy pool water.

How to Lower Alkalinity in a Pool

There are two ways to lower total alkalinity: using muriatic acid or using a pH reducer, a.k.a. sodium bisulfate. Keep in mind that whichever method you use will also lower your pH levels. And check out our guide on how to lower pH in a pool for more information.

How to Use Muriatic Acid to Lower Alkalinity

Pool-grade muriatic acid is similar to the hydrochloric acid that’s used to clean concrete and brick, but with a lower concentration of hydrogen chloride. It can help lower total alkalinity, remove calcium deposits, and clean filters. But it’s extremely corrosive and more dangerous to handle than sodium bisulfate.

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Used for lowering alkalinity and pH in your pool water. It's also used for cleaning pool filter grids, filter cartridges, and concrete pool surfaces.

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So because it’s an acid, always wear the appropriate safety equipment (including a mask to protect yourself from fumes) and follow the manufacturer’s directions on how to add the acid to your pool. Even though muriatic acid is somewhat diluted, certain brands require you to dilute it further before adding it to your pool.

1. Turn off your pool pump and wait until the water stops moving completely.
2. Calculate how much muriatic acid you need to add to your water. As a general rule, it takes 25.6 ounces of full-strength muriatic acid to reduce the alkalinity in a 10,000-gallon pool by 10 ppm.
3. Pour the muriatic acid into the deepest part of your pool and allow it to remain in the water for an hour.
4. Turn on your pool pump and let it run for at least 5 hours before testing alkalinity again.
5. After testing pool water alkalinity, retest your pH levels.

If you’re more concerned with lowering your pH than your alkalinity levels, here’s a chart to help you calculate how much muriatic acid to use.

Lowering alkalinity with muriatic acid won’t happen quickly. You may need to repeat the muriatic acid process after a few days if your levels aren’t within range. And if your alkalinity levels were literally off the charts, it can take several rounds of adding muriatic acid for your levels to appear within range.

If you need more help using muriatic acid, be sure to check out our complete guide on how to safely use muriatic acid in your pool.

How to Use Sodium Bisulfate to Lower Alkalinity

Sodium bisulfate, also known as acid salt or dry acid, is sold as pH down, pH reducer, pH minus, or pH decreaser. It works the same way as muriatic acid but it’s safer to use.

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However, though this method is safer to work with, it is more expensive. And you’ll still need to store the dry acid in a dry place protected from moisture.

Keep in mind that this will lower both your alkalinity and pH together, so be sure to retest both levels afterward.

• Follow the directions on the product to calculate how much to add to your pool water.
• Fill a bucket 3/4 of the way full with water and add sodium bisulfate.
• Use a wooden stick to mix the solution until the granules have completely dissolved. Any undissolved granules may sink to the bottom of the pool and destroy its surface.
• Carefully pour the dissolved solution around the pool’s perimeter, starting with a deep end.
• Retest the alkalinity and pH of your water. If necessary, repeat the procedure.

Frequently Asked Questions About How To Lower Alkalinity in a Pool

Need more help bringing your alkalinity into range? Here are some common questions and answers.

How do I bring the alkalinity down in my pool?

You can reduce the total alkalinity in your pool with a strong acid, such as muriatic acid or sodium bisulfate (pH decreaser). Pay attention to the directions on the bottle, measuring and mixing only what you need to bring your alkalinity levels back to the ideal range of 100 to 150 ppm.

What happens if the alkalinity is too high in a pool?

When alkalinity is too high in your swimming pool, your chlorine won’t sanitize the water as effectively. And it can lead to calcium buildup, and cloudy water and irritate a swimmer’s eyes and skin.

How do you lower alkalinity without lowering pH?

Total alkalinity and pH are so closely related that it’s very challenging to lower the alkalinity without lowering pH. So adding acid to the pool will reduce the total alkalinity, but it will also reduce your pH. If you need to raise the pH after using acid, you can aerate your pool water. This will bring the pH back up without affecting the alkalinity.

Does baking soda lower alkalinity in a pool?

No, baking soda will not lower your alkalinity levels. When you add baking soda or sodium bicarbonate to your pool water, it will raise both your alkalinity and pH. Baking soda is great for pool owners to have on hand as a substitute for alkalinity increaser. And soda ash, a.k.a. sodium carbonate, is another option for raising your alkalinity and pH. But again, neither will lower high alkalinity 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 Alkalinity Too High? Here’s How to Lower Alkalinity in a Pool Quickly appeared first on Swim University®.

Check out our video tutorial below or keep reading for the complete guide.

For a quick chemistry refresher: pH measures whether a substance is basic or acidic. The pH scale ranges from 0 to 14, where 7 is neutral, anything that measures below 7 is acidic, and anything that measures above 7 is basic. When properly balanced, your pool’s pH needs to be between 7.4 and 7.6.

Everything that enters the pool has the potential to affect pH level – even the swimmers themselves. Things like rain, dirt, and debris in your water can also knock things out of balance. And even salt water systems generate naturally high pH levels. So because pH is so volatile, it’s important to regularly test your pool’s pH levels as part of your pool maintenance routine.

Keep reading for a complete guide on what affects your pH and how to lower pH in a pool with pH decreaser or muriatic acid.

How Do pH and Total Alkalinity Affect Each Other?

Your total alkalinity and pH levels go hand in hand. And it’s your alkalinity that helps keep your pH level stable. Without this buffer, the pH would wildly fluctuate. When your total alkalinity is too low, the pH becomes unstable. And when it’s too high, it can bring up your pH levels with it.

That’s why adjusting your alkalinity before adjusting your pH is so important: it can help bring your pH into range. Your total alkalinity should be between 100 and 150 parts per million (ppm). If you find that your total alkalinity is too low, but you have a pH higher than 6.8, use an alkalinity increaser. If your total alkalinity is too high, using a pH decreaser or pH reducer like sodium bisulfate will bring down both your alkalinity and pH.

Still feeling confused about pool chemistry? Don’t worry, you’re not alone! We created the Pool Care Video Course to help pool owners master their water chemistry once and for all. Check it out!

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What Happens if Your Pool pH is Too High?

Once your pH level reaches 7.8 or higher, that’s considered high pH. And if your high pool water pH is left alone too long, can lead to a number of issues, including eroding pool parts and affecting swimmers themselves.

Reduces Chlorine Effectiveness

When the pH is too high, your pool’s chlorine won’t be able to clean the water as effectively. You’ll need to use more chlorine to get the same effect as before, which can affect the rest of your pool’s chemical balance. Without chlorine working effectively to kill microbes, you could end up with an algae bloom. And you may also end up with calcium buildup, which can lead to cloudy water and damaged pool equipment.

Irritates Eyes and Skin

High pH may cause swimmers to have itchy, red eyes. They may experience skin irritation, as well. So while many people think that high chlorine levels cause eye and skin irritation, it’s really high pH.

Erodes Swimsuits and Swimmer Gear

The high pH isn’t good for your swimsuits or goggles. Over time, the chemical imbalance may cause your swimsuit to fade, or degrade the fabric to the point where you can’t wear the suit anymore. Goggles may weaken and break sooner than you’d expect.

Damages Pool Equipment

The high pH will lead to calcium scale build-up, not just on the walls of your pool, but on your pool equipment, too. It’s possible the build-up will clog up equipment and block water flow in and out of the pool. This can introduce air into the pool pump, which will cause malfunction and may render it useless.

How to Lower pH with pH Decreaser (Sodium Bisulfate)

Most commercial pH decreasers, like pH Down or pH minus, are made with sodium bisulfate, also known as dry acid. They’re safer and less corrosive to use than muriatic acid, but they generally cost more.

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Avoid adding it to your pool on a windy day, since this increases the chance the powder will blow back into your face while using it.

1. Test Your Water

Start by testing your pH and alkalinity levels so you know how much you need to lower everything. If your total alkalinity is also too high, don’t worry: the pH decreaser will lower your alkalinity as well.

2. Measure Out the pH Decreaser

Read and follow the manufacturer’s directions to figure out how much ph decreaser you need to use.

It’s okay to use less and add more later. Remember, it’s easier to add more to correct your water balance than to adjust the pool chemistry if you add too much.

3. Add the pH Decreaser to Your Pool

Pour the chemical directly into your water near the return jets and in the deepest end of your pool. Keep the pump running. Do not add it to the skimmer. If you’re a pool owner with an above ground pool, you may need to help stir the water yourself with a pool brush.

4. Let the pH Decreaser Dissolve

Allow your pool’s filtration system to circulate the chemical throughout the water and dissolve. You may want to brush away any undissolved clumps off of your pool’s surfaces, or it can damage your pool walls and pool floor.

5. Retest Pool Water, Repeat As Needed

Immediately retesting your water isn’t necessary, but make sure you complete another test within 24 hours. If your pH and total alkalinity are within the normal range, congratulations! But, if you find they’re still high, repeat the process again.

How to Lower pH with Muriatic Acid

Muriatic acid, also known as hydrochloric acid, is a highly corrosive and dangerous chemical. So if you opt for this method to lower your pH, you’ll need to take extra precautions. Cover your body completely with clothing. And wear thick gloves, safety goggles, and a mask to avoid breathing in fumes. Even though it’s not a powder, you still want to avoid a windy day because of blowback and splashback.

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Used for lowering alkalinity and pH in your pool water. It's also used for cleaning pool filter grids, filter cartridges, and concrete pool surfaces.

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

1. Test Your Water

Test pH and total alkalinity so you know how much you need to lower both levels. Muriatic acid will lower both pH and alkalinity together. But they may decrease at different rates.

2. Measure Out the Muriatic Acid

Calculate how much muriatic acid you need to lower your pH to the normal range. If your pH reading is above 7.8 and you have a 15,000-gallon pool, start by adding 1 quart (1/4 gallon) of muriatic acid. Then after letting the acid circulate for one hour, retest your levels. If you have a smaller pool, start by adding one cup of muriatic acid at a time. Wait for one hour, then add more as needed. Check out our chart below on how much muriatic acid to add based on your pH levels and pool size.

3. Add Muriatic Acid to your Pool Water

Because this is an acid, it can damage your pool liner if it starts to collect in one place. So always run your filter to keep your water circulating (ideally on the circulate setting). Remember, you can always add more acid later so start slowly!

It’s easier and safer to handle muriatic acid if you dilute it in a bucket of water first. The ideal ratio of water to muriatic acid is 10:1 but always follow the manufacturer’s instructions. And be sure to add the water before adding muriatic acid to avoid splashback.

• Method One: Turn off the pool’s pump and add the muriatic acid in a small, steady stream directly into the deep end of your pool. This ensures the acid will go directly to the bottom, rather than floating around at the pool surface. Then turn your pump on and let it circulate the acid through the water.
• Method Two: Slowly pour the acid into the pool near your return jets and let the pump circulate it. For above ground pools, add the acid slowly by walking around your pool so it doesn’t get concentrated in a single spot.

If you want more help safely adding muriatic acid to your pool, be sure to check out our guide.

4. Let the Muriatic Acid Dissolve

Keep your pool’s filter running (ideally on circulate) and let the chemical dissipate. It should be dissolved within an hour. But it could take longer if you’ve had to add a large dose.

5. Test Your Water Again

Test the pH and alkalinity again after an hour or two. If the levels are still high, repeat the process again, adding a little bit of muriatic acid at a time.

It should be okay to swim after one hour of pool circulation if you’ve only added a little muriatic acid. But if you’ve added a larger quantity, wait 24 hours before retesting your water and swimming.

What If the pH and Alkalinity Won’t Balance?

It’s not uncommon for either your alkalinity or pH to remain unbalanced after adding pH decreaser or muriatic acid. You could have added enough muriatic acid to bring the pH into range, but your alkalinity is still too high. Or you’ve added enough acid to bring down your total alkalinity to the proper level, but now you have low pH.

If both your pH and alkalinity levels are too low, you can add soda ash to help bring them up. But what if you only need to bring your pH into range?

You can increase your pH levels without affecting your alkalinity by using pool aeration (see our pool aeration guide for more information). Using a water fountain or pool aerator will create bubbles that help outgas carbon dioxide in the water. As carbon dioxide leaves the water, the pH will rise without impacting your total alkalinity. And if you need to bring down your alkalinity, you can add more acid while aerating your water to keep your pH levels up.

Frequently Asked Questions About How to Lower pH in a Pool

Need more help lowering the pH in your swimming pool? Here are a few common questions and answers.

How do I lower the pH in my pool naturally?

Lowering a pool’s pH naturally can be done in four ways: installing a distilled water system to pump in water, cleaning your pool on a regular basis, leaving it alone, and letting the pH level come down on its own as minerals build-up, or installing a pool heater. The heated water will be able to dissolve natural substances better than cooler water. No matter what, you still need to use test strips or a testing kit to check levels regularly and prevent them from coming down too low.

What happens if pH is too high in a pool?

When the pH is too high in your pool, your chlorine won’t sanitize the water as effectively. Swimmers may experience eye redness and irritation. Bathing suits and goggles may fade and wear faster than normal.

Can you swim in a pool with high pH?

It’s not recommended to swim in a pool with high pH. When your pool’s pH is high, the chlorine won’t work as effectively to kill bacteria. And high pH levels can irritate swimmers’ eyes and skin.

Will shocking pool lower pH?

Adding shock can actually raise your pH levels. If you use a calcium hypochlorite (cal-hypo) shock, this can raise your pH levels temporarily. So test your chemical levels regularly, especially after shocking.

Does vinegar lower pool pH?

Vinegar contains acetic acids, which are helpful for lowering pH. However, the problem with this approach is that you would need a lot (several gallons) of vinegar to address pH issues in your pool. And when used in high amounts, the vinegar will leave behind sugars and other impurities. The sugars become food for microbes present in the water, and the impurities may affect your pool’s chemistry.

Will baking soda lower pH in a pool?

Adding baking soda to your pool will actually raise the pH and alkalinity of your pool water. Baking soda, better known as sodium bicarbonate, is naturally alkaline, with a high pH of 8.

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 Lower pH in a Pool Quickly with These Common Chemicals appeared first on Swim University®.

Pool-grade muriatic acid is similar to hydrochloric acid that’s used to clean concrete and brick – just with a lower concentration of hydrogen chloride. However, it’s still an acid, and it’s still highly corrosive. It can corrode everything from metal to plastics to clothing. It can also cause severe burns and injury when if it comes into contact with your skin, eyes, or respiratory tract if you inhale its fumes.

Even though muriatic acid is very useful and affordable to have around as a pool owner, it can be hazardous to handle if you’re not sure what you’re doing. So when should you use muriatic acid? And how much should you add to balance your water’s pH and alkalinity?

Here’s a simple guide on how to safely add muriatic acid to your pool. You can watch the quick video below or keep reading for a complete muriatic acid tutorial.

What Is Muriatic Acid Used For in Pools?

Muriatic acid is useful for lowering high alkalinity and pH levels in your water, cleaning cartridge filters or D.E. grids, and removing pool surface stains.

1. Lowers Total Alkalinity and pH

Muriatic acid can help balance your water chemistry by lowering the total alkalinity and pH levels in your pool. It’ll likely lower both levels together, since alkalinity and pH work hand-in-hand. But they may decrease at different rates.

Why is that? Since pH is naturally unstable in your water, it relies on alkalinity as a “buffer” to help prevent it from changing too much, too fast. So as your total alkalinity drops into its normal range (like after you add muriatic acid), it’ll help pull down your pH into its appropriate range, too.

If this kind of pool water chemistry has you confused, be sure to check out our guide on Basic Pool Chemistry 101.

So why is high pH and alkalinity a problem? If your pH is too high, it can cause cloudy water and your chlorine won’t sanitize as well. And less effective chlorine means a risk of algae blooms. High pH can also cause scaling, which can damage your filter system. Your pH levels should be between 7.4 and 7.6.

Similarly, if your total alkalinity is too high, it can also cause scale to build up inside your pool and filter system. It can also drag your pH levels up with it, throwing the rest of your water chemistry out of whack. Your alkalinity levels should be between 100 and 150 parts per million (ppm), with 125 ppm being ideal.

Now it’s important to note that high alkalinity levels will naturally decrease over time on their own. But high total alkalinity can precipitate other issues, like high pH and ineffective chlorine, which can lead to algae. So it’s often worth addressing high alkalinity levels before they can cause more trouble.

2. Cleans Cartridge Filters and D.E. Grids

If your pool uses a cartridge filter or D.E. filter, you may already have muriatic acid on hand. It’s commonly used to deep clean cartridge filters and it’s especially useful in breaking down the gooey residue that builds up in the pleats.

Muriatic acid is also very effective at cleaning diatomaceous earth or D.E. filter grids (or fingers if you have a Hayward D.E. filter). Calcium scale deposits can clog up the grid’s pores, but soaking it in a solution of muriatic acid can help break down any buildup.

We walk through how to clean your filters with muriatic acid at the end of this article.

3. Removes Concrete Pool Surface Stains

Muriatic acid is also a powerful stain remover. It can remove rust stains off of your pool’s surfaces, resurface your concrete pool deck, and clean the grout between your swimming pool tile.

However, as effective as it is in removing old, stubborn pool stains, it can be too harsh. Using acid can cause unnecessary corrosion and discolor your plaster. So be sure to test it on smaller pool surface areas first. And never leave a jug of muriatic acid out on your concrete deck: it could leave a ring!

By the way, if you’re feeling confused or overwhelmed by pool maintenance, check out our pool maintenance video course. It’s an easy-to-use guide for everything you need to know about keeping your pool clean and clear!

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

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Is Muriatic Acid Safe To Use?

When handled properly, muriatic acid is an extremely handy and affordable pool maintenance tool. But because it’s an acid, it’s incredibly important to follow some safety measures:

• Always wear face protection, including a respirator, acid-resistant gloves, eye protection, and fully-covering clothing. Remember, this highly corrosive acid can damage your skin, lungs, and eyes if the liquid or fumes come into contact with your body.
• Dilute your muriatic acid in water for the safest application. This means adding muriatic acid slowly and carefully to a bucket that’s already full of water. Never add water to acid, as that could kick up the acid onto you. And always use an acid-resistant plastic container.
• Store muriatic acid in the container that it came in. And always keep it away from other acids and pool chemicals. Never mix chemicals together!
• Keep a hose or water source nearby to wash your skin in case you accidentally splash yourself. And use baking soda to quickly neutralize any acid.

How To Lower pH and Alkalinity with Muriatic Acid

While buying a pH decreaser is an easy solution to lower both your pH and total alkalinity, muriatic acid is a cheaper option. pH decreasers, also known as dry acid, come in a powder form and are definitely milder than muriatic acid. They’re a little safer to use but more costly. Plus you may already have muriatic acid on hand for cleaning your pool filters and surfaces.

Before you start mixing up pool chemicals, you need the right safety gear. Remember, muriatic acid is extremely caustic. It can burn your skin in seconds, and the vapor from acid can cause serious respiratory problems without the proper protection.

You’ll need a few things to keep yourself protected:

• Safety goggles
• Acid-resistant gloves
• Chemical-resistant apron
• Plastic 5-gallon bucket
• Wooden or plastic stirrer

You’ll also need to buy pool-grade muriatic acid. Because it’s a hazardous material, it can be difficult to order online. But you can find it at your local pool stores. Some hardware stores carry muriatic acid for pools, but it’s usually a weaker formula.

​​Here’s the type of muriatic acid we recommend if you’re shopping online. It’s safer and easier to use than standard muriatic acid, but it can be more expensive:

Our Top Pick

Muriatic Acid for Swimming Pools

Used for lowering alkalinity and pH in your pool water. It's also used for cleaning pool filter grids, filter cartridges, and concrete pool surfaces.

Buy Now On Amazon

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

1. Test Your Pool Water

Before you add anything, you’ll need an accurate measurement of pH and total alkalinity in your pool. Test strips work pretty well, but digital test kits are even more precise.

No matter the reading, lowering your pool’s alkalinity with muriatic acid is best done in stages, adding no more than ½ gallon of muriatic acid at a time. So plan to retest your water throughout this process.

2. Calculate How Much Muriatic Acid to Add

First, you’ll need to know how many gallons of water your pool holds. If you’re not sure about the volume of your pool, you can use our pool calculator.

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

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The label on your muriatic acid should help you determine how much acid to add. But if it doesn’t, you can plug your figures into an online calculator or use the chart below.

Aim to bring your pH down to just below the optimal range. This should be enough muriatic acid to bring your alkalinity down to normal. In general, 20 ounces of acid will lower the alkalinity in a 10,000 gallon by 10 ppm.

But what happens if your pH drops too low after adding muriatic acid? If you need to nudge your pH upward, you can run your pump to aerate your pool and gently bring your pool pH levels up.

Remember, you can always add more muriatic acid if you need to. So start slowly and add only up to ½ gallon of muriatic acid at a time.

3. Turn Your Pump To Circulate

Set your pool pump to circulate before adding muriatic acid. This will help disperse the acid in your water when you add it.

You should also turn off any water features, including aerators and fountains. Air in your water can raise your pH, which is the opposite of what you’re trying to do at this stage!

4. Add the Muriatic Acid

Diluting the muriatic acid in a bucket of water makes it easier and safer to handle. The ideal ratio of water to muriatic acid is 10:1 but always follow the manufacturer’s instructions.

First, add water to an acid-resistant bucket. Then add the appropriate ratio of acid, stirring it gently with a plastic or wooden stir stick. Always add water to your bucket first, not acid. If you add the acid first, you run the risk of splashback.

Also, be sure to rinse your muriatic acid bucket thoroughly after every use, and do not use it for any other pool chemicals. You could cause a chemical reaction or explosion.

If you do want to add muriatic acid directly to your pool, start by pouring the muriatic acid into the deep end of your water. Be sure to walk away as you pour so you don’t inhale the fumes.

5. Let the Muriatic Acid Circulate

Keep your pump on for at least 30 minutes immediately after adding the muriatic acid. Again, be sure your pump is set to “circulate” to help the muriatic acid mix in. This will prevent the acid from damaging your pool surfaces.

Some pool owners leave their pumps off during this time and let the acid concentrate to better affect their alkalinity levels. This approach is called pooling. But remember: muriatic acid is extremely caustic and will eat into your pool floor if you leave it to settle. You’ll need to constantly brush the pool floor to prevent the acid from doing damage. That’s why we recommend turning on your pump to circulate the water at this phase.

6. Retest Your Pool Water

Retest your water after a few hours. You should notice a difference in your water chemistry at that point. If your alkalinity hasn’t gone down far enough, you can add another dose of muriatic acid.

Keep testing and adding muriatic acid in doses of ½ gallon or less, repeating as many times as necessary to get the alkalinity back down. It’s not unusual for it to take a couple of doses.

But if you can’t seem to get your alkalinity and pH under control, take your water to your trusted pool store for testing. Your problem could be one of testing accuracy, not actual chemistry.

7. Aerate Your Pool

If your pH dipped too low but your alkalinity reading is good, you can aerate your water. Adding air is a natural way to raise your pH without having to chemically bring your pH back up. Chemicals like pH increaser end up raising alkalinity as well – and you’re back to the problem you had when you started!

To aerate, turn your return jets upward and turn your pump on its highest setting. And turn on any water features you have as well, like an aerator or a fountain.

Then check your pH again in another day to see if it’s risen up to normal levels. If the pH still needs to be increased significantly, you may actually need a chemical pH increaser. Just be sure to add a little bit at a time, since it can affect alkalinity.

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How to Safely Clean Your Filter with Muriatic Acid

A 20:1 ratio of water to muriatic acid is usually sufficient for cleaning your cartridge or D.E. filter grids. Just be sure to follow all of the safety steps mentioned before. Regardless of what type of filter you have, the process is generally the same:

1. Remove the cartridge filter or filter manifold.
2. Use a spray nozzle on your garden hose to spray down the cartridge or manifold, making sure to get between the pleats.
3. Fill a large, acid-proof bucket with water. Then add the correct ratio of muriatic acid (20:1 water to acid). Make sure the cartridge or grids are completely submerged.
4. Let the cartridge or grids soak overnight. Then rinse it thoroughly, spraying it with a hose.
5. Return the cartridge or grids to your filter and secure it in place.

For more help cleaning your cartridge or D.E. filter, check out our Filter Cleaning Guide.

Frequently Asked Questions About Muriatic Acid

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

How long does muriatic acid take to lower alkalinity?

You’ll likely notice a difference in your water chemistry an hour or two after the muriatic acid has circulated. Retest your water at that point. If your pH and alkalinity levels are still too high, add another round of pool acid in ½ gallon doses or less. Remember you can always add more, so take your time.

Is muriatic acid the same as cyanuric acid?

No, these are different. Other types of acids used in pools, like cyanuric acid, aren’t used for adjusting pH or alkalinity levels like muriatic acid.

Can you pour muriatic acid directly into a pool?

Yes, you can add muriatic acid directly to your swimming pool water. But it’s safer if you dilute it in a bucket of water first. If you do want to add it directly to your pool, pour it into the deepest part of the pool, walking away as you pour so you don’t inhale any of the fumes. And always wear the appropriate safety gear.

How much muriatic acid do you put in a pool?

If your pH levels are above 7.8 and you have an average-sized pool (15,000 gallons), you’ll need about a quart (or ¼ gallon) of muriatic acid to bring your levels within range. There are usually dosing instructions on the label of pool-grade muriatic acids. Otherwise, you can use this online calculator or the dosing chart below.

What happens if I put too much muriatic acid in the pool?

Adding too much muriatic acid can drop your pH levels too low. Low pH can cause eye irritation and skin rashes. It can also erode metals like pool ladders, railings, nuts and bolts, and other pool equipment.

If you accidentally add too much muriatic acid and your pH levels have dropped too low, you can raise them back up with soda ash or pH increaser. And if you haven’t added your muriatic acid yet, go slowly. You can always add more later after you retest your water.

When can I swim after adding muriatic acid?

To be safe, wait at least an hour for the muriatic acid to dissipate, then retest your pool water before swimming again to make sure your pH isn’t too low. Adding muriatic acid directly to your pool can create an “acid hot spot” in the water. This can burn or irritate your skin, eyes, nose, and throat if you swim too early. The longer you wait, the safer it is.

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 How to Safely Use Muriatic Acid In Your Pool appeared first on Swim University®.

Baking soda raises alkalinity levels in your pool. AND it can be less expensive than Alkalinity Increaser.

Understanding pH Levels and Total Alkalinity in Your Pool

You can either have acidic water or basic pool water. The level of how acidic your pool water is is determined by the pH scale.

The lower the pH level, the more acidic your water will be. Acidic water can cause long-term damage to all your equipment and pool surfaces by eating away at it over time.

The higher the pH level, the more basic your water will be. Basic water can also cause damage by adding a layer of film (or scaling) to your pool parts. Do you know that white, crusty build-up you sometimes see on showerheads? That’s what can happen to your pool and all its equipment.

Here’s a visual of the pH scale. Pool water can be as low as 6 or as high as 8. Your goal is to keep it neutral. Which for a swimming pool is between 7.4 and 7.6.

Now, alkalinity is your pH buffer. But I like to call it pH’s bodyguard. Having the alkalinity of the water between 100 and 150 ppm (parts per million) will help keep a stable pH.

For example, every time it rains or when someone jumps in the pool, that can affect your pH. It can cause it to go up or down dramatically. But alkalinity will take the brunt of the hit before your pH does. And that’s why it’s important to use the right amount of baking soda to keep both your pH and alkalinity levels correct.

How Much Baking Soda Do I Add To My Pool?

As a rule of thumb, use 1.5 pounds (680 grams) of baking soda per 10,000 gallons (37,854 liters) of pool water. This should raise the alkalinity by about 10ppm (parts per million). Or you can use the chart below.

If you’re not sure how much water your pool holds, check out our pool calculator.

Once you know your pool’s volume, and you’ve measured out the baking soda, don’t add it all at once! If you adjust the alkalinity too much in either direction, it can affect the pH as well.

Note: It doesn’t matter which type of baking soda you use. The most popular brand is Arm & Hammer, which is a good choice. Any grocery store brand will do as long as the main and only ingredient is Sodium Bicarbonate.

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How to Add Baking Soda to Your Pool

1. Start by adding just 1/2 or 3/4 of the baking soda you’ve measured out. Distribute it in wide arcs across the entire pool. This is called “broadcasting.” Wear chemical-resistant goggles and gloves. And it’s best not to do this on a windy day.
2. Let the baking soda circulate and dissolve for at least six hours. Keep the filtration system running during that time. Then using a liquid test kit or test strips, check both the total alkalinity and pH levels.
3. If the levels are still off, repeat the process. If they’re where they should be, congrats! You just saved money taking care of your swimming pool!

Note:  We don’t recommend adding baking soda directly into your skimmer. Adding chemicals through your filter system can be dangerous especially if you have a chlorinator or chemical feeder. It’s actually easier to just add it directly to the water.

If any of this is confusing so far, don’t worry. Pool chemistry can seem overwhelming, but it’s actually really easy if you just have the right education and some tools at your disposal. That’s why we created our own pool maintenance video course to teach you everything you need to know about chemistry, cleaning, and troubleshooting.

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Baking Soda Vs. Soda Ash

Baking Soda (Sodium Bicarbonate) is used to raise alkalinity and also slightly raise pH. And Soda Ash (Sodium Carbonate) is used to raise pH and slightly raise alkalinity.

For example, getting a pH reading around 7.2 to 7.6 in 10,000 gallons (37,854 liters) of pool water would take roughly 21 pounds of baking soda. This would also increase the Total Alkalinity by roughly 150 ppm (parts per million). And that’s way too much!

But if we wanted to increase the pH of the pool by 0.5, we could use roughly 12 ounces (340 grams) of soda ash. That would only increase the total alkalinity by roughly 8 ppm.

In other words, use baking soda to increase alkalinity and soda ash to increase pH.

Are There Any Risks With Putting Baking Soda in Your Pool?

While there’s no risk in using baking soda in your pool, there are risks to having high and low alkalinity.

You might notice corrosion in and around your ladders, liner, tiles, or other parts of your pool. This is likely due to low pH and alkalinity for long periods of time.

And if you see scaling or a build-up around your pool equipment, this could be caused by high pH and alkalinity. And it means your water is hard.

All you have to do is keep the alkalinity between 100 and 150 ppm and the pH between 7.4 and 7.6 as often as possible. Test your pool water daily and adjust your chemical levels when needed.

What About Health Risks?

We mentioned getting it in your eye if you add it to your pool on a windy day. That hurts like hell. But besides that, sodium bicarbonate (aka baking soda) is relatively safe.

Sodium bicarbonate has been used for thousands of years. Most notably by Ancient Egyptians who used it to clean their teeth. Just like we do today!

And it’s “Generally Recognized as Safe” by the FDA as a direct food additive.

Think of it this way, if it’s safe enough to use in cakes, then your swimming pool won’t be a problem.

Baking Soda In Pool Water Will Save You Money

The best part about all this is that baking soda is often cheaper than an alkalinity increaser. And you can buy baking soda in bulk just like the pool supply store brand.

On top of that, you can always use any extra baking soda to brush your teeth, make a cake, or clean your dishes.

Happy Swimming!

The post How To Raise Your Pool’s Alkalinity with Baking Soda appeared first on Swim University®.

This article will give you a step-by-step guide on how to raise ph in your pool with three inexpensive solutions: Soda ash, baking soda, or pH increaser.

How to Test Your Pool’s pH Level

You can test your pool water with strips, a liquid test kit, or an electronic meter. No matter how you plan to test your pool water, make sure to take a sample using a clean bottle. Avoid pulling a sample near skimmers and return jets. Ideally, you want to grab a sample from the middle of your pool.

Test The pH Using Strips

Strips are the easiest to use but tend to be the most inaccurate. I still rather use test strips than not testing at all. They’re also pretty cheap. So if testing is a pain for you, then use test strips.

I like test strips that test for pH, Alkalinity, Chlorine, CYA, and Calcium Hardness.

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Test The pH Using a Liquid Test Kit

A liquid test kit is a lot more accurate but requires a little more work. You have to pull a sample of water and add a few drops of liquid. Then match up the color to the correct pH level. Just follow the directions on the liquid test kit.

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Test The pH Using a Digital pH Meter

A digital pH meter is a little more expensive but it’s worth the investment. A digital pH meter requires you to put your probe in water and press one button to get instant results of your pool’s pH levels.

To use a digital pH meter, you have to calibrate the device with some liquid or buffer solution. The calibration instructions will be included in the package for your specific model of digital pH meter.

After calibration is complete, just dip your probe into a clean sample of pool water and wait until it gets an accurate reading on the screen!

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How to Raise Your Pool’s pH Level with the Right Chemicals

For balanced pool water, keep the pH between pH of 7.4-7.6. And there are two different chemicals you can use to raise the pH in your pool:

• Baking Soda aka sodium bicarbonate (sold as Alkalinity Increaser in pool stores).
• Soda Ash aka sodium carbonate (sold as pH Increaser in pool stores).

Note: Before you add any chemicals to your pool, make sure you know exactly how much water your pool holds so you add the correct amount of chemicals to raise your pH and other levels.

Click which type of pool you have to start the calculator below.

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

Rectangle

Round

Get Pool Volume

Get Pool Volume

If you decide to use baking soda, just note that this chemical will also increase your alkalinity level. So if both your pH and alkalinity are low, this is the right chemical to use to raise each one.

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But if you just want to raise your pH level, then you should use soda ash.

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How to Add The Right Chemicals to Raise your Pool’s pH Level

Thankfully, adding baking soda and soda ash is really easy.

1. Make sure your pump and filter are running so that the chemical is mixed into the pool water properly.
2. Add a small amount of the chemical right into the pool. Be sure to spread it around as much as possible and don’t add too much all at once.
3. Let the chemical dissolve into the pool and circulate before adding more.

The act of adding any powder directly to the pool water surface is called broadcasting. You’re broadcasting the chemical around your pool.

It takes about 20 minutes after stirring to see results. Check out how much baking soda or sodium carbonate (soda ash) is required based on your pool’s current readings!

Why Your Pool pH Balance Is Important

If your pool’s pH balance is off, there are some very specific causes and effects. Low ph levels in a pool may lead to:

• Erosion of the metal liner or concrete walls (pools with plaster linings) from acid corrosion
• Reduction in the effectiveness of disinfectants like chlorine or bromine.
• Excessive growth of algae and bacteria in your pool.

Here’s a pH chart that shows how acidic or basic the scale represents.

Overall, having balanced pool water (perfect pH and alkalinity levels) helps keep your pool clear and also makes your sanitizer work better. And if your water is too acidic (low pH) it’ll corrode pool equipment and wear down the liner, requiring more frequent replacements.

What Causes Low pH Levels

Mostly low pH levels come from natural factors like rain. The natural pH of rainwater is about 5. So after a heavy rainstorm, it’s normal for your pool to have a lower pH. It’s a good idea to test and rebalance after each storm.

Low pH can also happen after a large party or just having a ton of people in your pool in a short period of time. The more people in your pool, the lower the pH will go. This is caused by dissolved bodily fluids. Gross, I know.

Balanced Water is the Key to a Clean and Clear Swimming Pool

All pools need to be tested and balanced on a regular basis with basic pool chemistry. The key is understanding the pool’s pH level, which will determine how acidic or basic your water is. If you know what balance of chemicals your pool needs for proper maintenance then all you have to do is follow our quick tips for maintaining it!

This includes keeping an eye on the chlorine levels as well as adding in the right amount of algaecide or shock treatment each week.

For those who want more information about how to keep their pool clear and healthy without too much effort, we recommend downloading this helpful cheat sheet that highlights our top 10 best practices for maintaining your swimming area with ease!

Happy Swimming!

The post How To Raise The pH Level In Your Pool: The Easy Way appeared first on Swim University®.

All good questions. And it’s your lucky day, because we’ve got all the answers. Learning how to manage and control the calcium level in your pool is a big step toward keeping it clean, clear, and swimmable all season long.

What Is Calcium Hardness?

You’ve heard of hard water, right? You may live in an area where the municipal water is hard. Or you may even get your water from a well. Either way, it means your water supply has a high level of minerals, including calcium.

But wait, calcium’s a good thing, isn’t it? It makes strong, healthy bones and teeth. Sure, that’s true. But it’s not so good for your pool and all the expensive equipment you bought to keep it clean and healthy.

Over time, an out-of-whack calcium hardness level can do some real damage, which is why it’s so important to monitor and balance the calcium hardness in your pool.

What Is the Correct Calcium Hardness Level?

Here’s your favorite answer: It depends. But what it depends on isn’t that difficult.

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.

See? Easy.

The key is keeping it balanced. You don’t want your pool water to be too hard or too soft. Either way, you’re in trouble.

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What If the Water Is Too Hard?

If the calcium hardness level in your pool gets too high, the water will be hard. The first indication will likely be a cloudy pool.

Normally, you can clear cloudy pool water with pool shock. But if the cloudiness doesn’t dissipate after shocking, especially if you try it a couple of times, it could be too much calcium in the water.

If left unaddressed for too long, you may also notice a buildup of calcium sediment on pool surfaces. When that happens, it’s time—past time, really—to reduce the amount of calcium in your pool.

How to Lower Calcium Hardness in Your Pool

Once you test the water and determine the calcium level is too high, you’ll need to bring it down.

• Drain and replace some water. Before you replace the water, test your water source. If it’s high in calcium, try using a hose filter to keep some of the minerals out. Otherwise, this will be an exercise in futility.
• Use pool flocculant. If you can’t or don’t want to drain any water from the pool, try using pool floc to clump the excess calcium. Once the clumps form, you’ll need to manually vacuum your pool to remove them. Important: Be sure to turn your pump and filter off before putting floc in the water. You do not want to get any flocculant in your filter, or you’ll need to replace the filter medium. To that end, you also need to ensure you vacuum to waste. This means you can’t use floc if you have a cartridge filter.
• Try muriatic acid. If draining and floc don’t work, you can add muriatic acid as a last resort. It won’t actually reduce the water’s calcium hardness, but it will raise the saturation level, which can help bring the water back into balance.

What If the Water Is Too Soft?

How is this even possible? How can water be too soft? Well, when it’s the water in your pool, it’s definitely a concern.

Too-soft water will be corrosive to your pool. It can dissolve concrete and plaster, and corrode any metal parts submerged in or touched by the water. It all amounts to expensive repairs if you don’t bring the calcium hardness level back up.

How to Raise Calcium Hardness Levels

Good news! Bringing the hardness level up is much easier than lowering it. All you need to do is add a calcium hardness increaser to your pool. Be sure to carefully follow the instructions on the package in order to obtain the best results.

To add the proper amount of hardness increaser, you’ll need to know your pool’s volume, which you can easily determine with a pool calculator.

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

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Get Pool Volume

Get Pool Volume

How to Get It Juuuust Right

Of course, the best way to avoid any calcium hardness problems is to maintain your pool, keep the water balanced, and prevent the calcium from getting too high or too low.

• Keep your pool clean.
• Balance the water. Keeping a close eye on your pool chemistry will help you prevent problems related to calcium hardness, and a lot of other things as well.
• Test the water frequently. This is especially important if your water source is hard. Testing every week—every two weeks at most—will help you stay on top of things. Be sure to choose test strips that include calcium hardness, or get a liquid test kit.</
• Address problems early. Don’t wait for water hardness to get out of hand before you try to fix it. As soon as you see the level creeping a little too close to the lower or upper limit of the appropriate range for your pool, take action.

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Balancing Calcium Hardness Isn’t That Hard

It just requires some vigilance on your part. Pool maintenance just isn’t an area where you can slack off and expect things to be fine when you get back into your routine. The longer you let the water chemistry languish, the more likely it is that you’ll have trouble with calcium hardness, and any number of other things.

Owning a pool should be fun. The better you care for your pool, the less work it will be, and the more you can enjoy it.

Happy Swimming!

The post How to Balance the Calcium Hardness Level in Your Pool appeared first on Swim University®.