But before buying a salt water hot tub system, it’s important to know the difference between a salt water spa and a traditional hot tub. Check out the video below or keep reading for a complete guide on salt water hot tubs, including how to convert to a salt water system.

What’s the Difference Between a Salt Water Hot Tub and a Traditional Hot Tub?

A salt water hot tub sanitizes your spa by using salt that’s added directly to your water vs. adding chlorine or bromine to your water. This is done through a salt water chlorinator or chlorine generator that converts salt to chlorine.

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That’s right: a salt water hot tub still contains chlorine or bromine. You’re just getting those chemicals into your water in a different way. Instead of buying, storing, and adding harsh chemicals to your water, you’re adding salt.

After installing a salt water system, it’s unlikely you’ll even be able to taste the salt in the water. Sea water has a salinity of about 35,000 parts per million (ppm). The recommended salinity level for a salt water hot tub is between 2,000 ppm and 3,000 ppm.

So as long as you add the appropriate amount of salt to your hot tub, and keep your water balanced, the salinity will be undetectable. For a salt water hot tub, you need about 2 1/3 cups of salt per 100 gallons of fresh water. That’s about 11 cups of salt for a 500-gallon hot tub.

By the way, if you need more help with hot tub maintenance, be sure to check out our Hot Tub Video Course!

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How Does Hot Tub Salt Become Chlorine?

Salt water chlorinators, chlorine generators, or bromine generators (if you prefer bromine to chlorine) contain a chlorinator cell composed of titanium plates and electrodes. When placed into properly salinated water, the chlorinator cell uses a minuscule, safe amount of electricity to transform your water’s salt solution into chlorine (or bromine) via a process called electrolysis. Here’s what a typical salt water system looks like:

Saltron Salt System Chlorine Generator for Hot Tubs & Swim Spas

This drop-in chlorinator lets you convert any hot tub or swim spa up to 2,000 gallons. Simply plug in the controller above ground and out of the water while immersing the chlorinator cell in water.

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For the generator to work, you’ll need to add pool salt or hot tub salt. If you see it labeled as “pool salt,” that’s perfectly fine to use in your hot tub. This salt is chemically the same thing as table salt, but it’s a coarser grind to work better in a chlorine or bromine generator. So only add pool-grade or spa-grade salt to your water. If you want bromine in your water, you’ll want to add sodium bromide salts.

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Benefits of Salt Water Hot Tubs

Switching from other hot tub sanitizing methods has a few big payoffs. A salt water spa can be less maintenance and a smoother soaking experience.

Consistent Bromine or Chlorine Levels

Since salt water systems continuously monitor your chlorine or bromine levels, they’ll only generate as much sanitizer as your water needs. That helps prevents extreme fluctuations and helps eliminate that nasty chlorine smell in your water.

Gentler Soaking

Chloramines—the chlorine byproducts that can cause burning eyes and breathing difficulty—are reduced in a salt water hot tub. Because the chlorinator is continuously creating a small amount of chlorine, the sanitizer level remains more stable to keep chloramines at bay.

Also, salt water is softer water than traditionally chlorinated water, so it’s easier on the skin, hair, and eyes. And if you use bromine, all of these benefits are increased.

Less Maintenance Time

Salt water spas have a steady concentration of sanitizer being added all the time, so the overall hot tub water chemistry may need less adjusting. And you won’t have to constantly buy, handle and add chlorine or bromine. But regular water care, like testing and balancing pH, is still required.

Reduced Cost

Bags of salt are less expensive than chlorine or bromine, plus they’re easier to handle. And after the initial dose of salt, your hot tub’s salinity will stay relatively steady unless it’s diluted with rain or you’ve added fresh water. This means you won’t need to buy salt as often as you would chlorine or bromine.

You’ll still need to test your water on a regular basis to ensure it’s balanced. In addition to using standard test strips you’ll use for pH, alkalinity, etc., you’ll also need to manually test for salinity every month. This is to ensure your salt water generator is reading your levels correctly. You can buy salt water-specific test strips or use a digital salinity reader.

Salt Water Test Strips for Pools and Hot Tubs

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Salt Water Hot Tub Myths Debunked

Despite the many wonderful benefits of switching to salt, a few myths persist.

Myth #1. It Requires No Maintenance

All hot tubs require maintenance, no matter what you use to sanitize them. No system is truly “set it and forget it.” And chlorinator cells must be replaced every one to three years. Until then, they need to be cleaned regularly.

Typically, cells are cleaned by soaking them in muriatic acid but always defer to the manufacturer’s recommended maintenance for your model.

Myth #2. It’s Chemical Free

While you don’t need to buy or add chlorine or bromine to a salt water hot tub, the end result is still water that contains chlorine or bromine. You’ll also still need chemicals like non-chlorine shock and balancing chemicals, such as pH increaser or pH decreaser, to keep your water chemistry balanced.

Myth #3. It’s Corrosion Free

Despite its low salinity, the salt water in a hot tub can cause corrosion of metal components. For example, your hot tub’s heating element may not be suited to salt and could corrode quickly if it isn’t a titanium-coated element.

Wiping down exposed metals frequently and making sure your water isn’t over-salinated can help prevent corrosion.

What are the Different Types of Salt Water Systems?

The good news is that almost any hot tub can be converted into a salt water hot tub by simply adding a salt chlorine generator.

Before you can convert to a salt water hot tub, you need to decide what kind of salt water chlorinator you want to use: an in-line system or drop-in. Both use electrolysis to create sanitizer from salt but have a couple of important differences.

Drop-In Chlorinators

Saltron Salt System Chlorine Generator for Hot Tubs & Swim Spas

This drop-in chlorinator lets you convert any hot tub or swim spa up to 2,000 gallons. Simply plug in the controller above ground and out of the water while immersing the chlorinator cell in water.

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

The easiest way to convert to a salt water hot tub is with a drop-in chlorinator. No permanent alterations to the spa are necessary for installation. And setting it up takes minutes. The only drawback is you’ll have a thin cord connected to the chlorinator cell that hangs over the side of your hot tub.

In-Line Chlorinators

If you don’t want a chlorinator line hanging over the side of your hot tub, you can get an in-line salt water conversion kit. This type of chlorinator must be spliced directly into the hot tub plumbing, so the cell becomes part of the spa’s circulation system.

Important: If you’re not an experienced plumber, you may want to hire a pro for in-line installation. Also, these kits may void your hot tub warranty, so check with your spa manufacturer before installing one.

How to Convert to a Salt Water Hot Tub

We’re going to cover how to install a drop-in chlorinator. If you’ve chosen to use an in-line generator, follow the manufacturer’s installation instructions or hire a professional to ensure proper installation. With a drop-in system, it usually takes more work to prepare your hot tub for conversion than it takes to do the actual conversion.

You’ll need:

• Drop-In Salt Water Chlorinator
• Spa Line Flush
• Garden Hose
• Sump Pump (optional)
• Filter Cleaner (or a new filter)
• Hot Tub Surface Cleaner or White Vinegar
• Non-Abrasive Scrub Sponge or Soft Cloth
• Hose Filter
• Salt Water Test Strips
• Hot Tub Salt
• pH Increaser (if needed)
• pH Decreaser (if needed)
• Alkalinity Increaser (if needed)
• Alkalinity Decreaser (if needed)
• Calcium Hardness Increaser (if needed)
• Screwdriver

1. Drain and Clean Your Hot Tub

Before switching from one sanitizing method to another, you must remove all residual sanitizer and any contaminants. Use a spa line flush before you drain and clean the hot tub. This will help clear out biofilm. If you need more help using line flush, be sure to check out our guide on How to Drain and Clean a Hot Tub.

After using the line flush, drain the hot tub with the hose or sump pump. Clean the shell with hot tub cleaner or diluted vinegar and a non-abrasive scrub sponge. Then rinse thoroughly and wash or replace the filter.

2. Refill the Hot Tub

Attach a hose filter to your garden hose to refill your spa with clean, filtered water. The filter helps remove minerals and metals before they get into your spa.

3. Test the Salinity and Add Salt

Before adding anything to the fresh water, test the salinity. Tap water naturally has a small amount of salt in it, so testing first will help you avoid adding too much salt.

Follow the product instructions for adding enough salt to obtain the proper saline level. In general, you need about 2 1/3 cups of salt per 100 gallons of fresh water.

4. Test the Water Chemistry

Test your pH, alkalinity, or calcium hardness and make sure they’re in range based on the recommendations in your chlorinator manual. If anything needs tweaking, adjust it now. And if you need more help with water chemistry, be sure to check out our Hot Tub Chemistry Guide.

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You’ll also want to add an initial small dose of chlorine or bromine to the water when starting it up for the first time. Salt system manufacturers recommend this to help your system maintain the proper chlorine or bromine levels. You may need to add an initial dose when you drain and refill your hot tub in the future.

5. Mount the Chlorinator Control Panel

The chlorinator conversion kit should contain a control panel and hardware for mounting it. Place it on the side of your hot tub or a nearby post, making sure the power supply cable will reach your GFCI (ground-fault circuit interrupter) outlet and the chlorinator cell will reach the spa.

6. Attach All the Cables

Connect the power supply cable and chlorinator cell cord, but do not plug the power cord into an outlet yet.

7. Place the Chlorinator in the Hot Tub

Drape the supply cord over the side of your spa, then place the chlorinator into the deepest part of your hot tub. Putting it as low as possible helps distribute the sanitizer more evenly.

8. Plug in and Start the Generator

Plug the power supply cord into the GFCI outlet. Then turn your chlorinator (or brominator) on. Follow the manufacturer’s instructions to program your generator.

Frequently Asked Questions about Salt Water Hot Tubs

Need more help with salt water hot tubs? Here are several common questions and answers.

How much salt do I need to add to a salt water hot tub?

For a freshly filled hot tub, you need about 2 1/3 cups of salt per 100 gallons of fresh water. That’s about 11 cups of salt for a 500-gallon hot tub. Remember: you can always add more salt, so add it slowly and retest your water. You’ll have to drain out some of your water if you add too much.

What’s the best salt water hot tub?

Caldera Spas and the Freshwater Salt Systems by Hot Spring Spas both manufacture hot tubs with built-in salt water systems. But you can also buy a salt water system separately and install it on your own.

Can I use bromine in a salt water hot tub?

A salt water hot tub can produce either bromine or chlorine, but you’ll need to by a salt water brominator and sodium bromide salts. These are more expensive than a salt water chlorinator system and salt.

Can I use any salt in my salt water hot tub?

No, you must use pool-grade or hot tub-grade salt. Salts made for other uses can introduce contaminants and impurities such as heavy metals. Table salt, rock salt, Epsom salt, and even some products marketed as natural such as pink Himalayan salt, are best left out of your hot tub. Not only can they mess up your water chemistry, but if they damage your spa, there’s a good chance you will have voided the warranty. Make sure you only use salt meant for chlorine (or bromine) generators.

Need More Hot Tub Maintenance Help?

• Download our free Hot Tub Cheat Sheet. It’s a free, easy-to-use guide to help you keep your hot tub clean and clear.
• Subscribe to our Swim University YouTube Channel. We publish free video tutorials about hot tub care.
• Check out our Hot Tub Video Course. You’ll get step-by-step videos and a downloadable guide with everything you need to know about hot tub maintenance.

The post Salt Water Hot Tubs: How to Convert Your Spa and Use Fewer Chemicals appeared first on Swim University®.

So here’s a complete step-by-step walkthrough on which hot tub chemicals are definitely required, which ones you can skip, and how to add each chemical to your hot tub (and in what order).

You can watch the quick video below or keep reading for the complete guide on spa chemicals.

What Chemicals Do You Need for a Hot Tub?

If you want to keep your hot tub water balanced and avoid major problems like algae, bacteria, and biofilm build-up, you’ll need to have these hot tub chemicals on hand:

• Hot tub sanitizer, like chlorine or bromine
• Hot tub shock
• Alkalinity increaser
• pH increaser
• pH decreaser
• Calcium hardness increaser
• Line flush cleaner
• Water clarifier, metal sequestrant, filter cleaner (optional)

Before you add anything to your hot tub, you’ll need to test your water. You’ll want a good supply of test strips. Or for more accurate results, you can use a liquid test kit. You can also take a water sample to your local pool and spa store if you want to test your water source for metals or other minerals. Now after you have your baseline readings, you can start adding your chemicals.

Here are the right hot tub chemical levels:

By the way, if you’re feeling overwhelmed by hot tub water chemistry, check out our Hot Tub Video Course. It’s an easy-to-follow guide to help you save time and money on hot tub maintenance.

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1. Hot Tub Sanitizer

First, you’ll need to decide which type of sanitizer you want to use: chlorine, bromine, biguanide, minerals, or a saltwater system. Each one has its pros and cons. But the biggest debate is whether to use chlorine or bromine.

• Chlorine: Many outdoor hot tub owners use chlorine to sanitize their water. It’s cost-effective, easy to add and manage and it’s an aggressive bacteria and algae killer. The downsides? That chlorine smell. Chlorine kills contaminants by oxidizing. But as this chemical reaction occurs, it gives off waste products called chloramines that cause that smell. If you can smell chlorine, it probably means your chlorine has been used up in your water and you need to add more. Remember, the proper chlorine level for a hot tub is 1 to 3 ppm.

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• Bromine: Bromine doesn’t produce that chlorine-like smell in your hot tub. It also lasts longer than chlorine and has a lower pH, making it a little easier to keep the water balanced. And many hot tub owners prefer using it because it’s gentler on your skin. But it tends to work more slowly. It’s also unstabilized. That means if you use it in an uncovered, outdoor hot tub, it’ll burn off pretty quickly under the sun. Bromine is best for indoor hot tubs, or hot tubs that aren’t in direct sunlight. The proper bromine level is 3 to 5 ppm.

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If you want to learn about more sanitizer options, be sure to check out our other in-depth guides on mineral systems and saltwater systems.

2. Hot Tub Shock

Hot tub shock is a great problem-solver and a must-have for regular hot tub maintenance. It provides a large dose of sanitizer to help ward off any developing water issues.

So if you see algae starting to bloom or you notice cloudy hot tub water, your hot tub shock will help. And a weekly shock treatment is a great way to help refresh your sanitizer levels and prevent issues down the road.

There are two types of shock: chlorine shock and non-chlorine shock. And they both have different applications:

• Chlorine or bromine hot tub: Use either chlorine or non-chlorine shock. If you use a non-chlorine shock, you’ll be able to use your hot tub a lot sooner after you shock it. But chlorine shock is more effective at killing algae or bacteria, so that’s what we recommend.

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01/27/2023 09:00 pm GMT

• Mineral hot tub: We recommend using non-chlorine shock to keep your chlorine levels low.
• Saltwater hot tub: Use chlorine shock. If you’re worried about your chlorine levels being too high, it’s okay to use a non-chlorine shock.

If you want more information on what type of shock to use, check out our complete guide on How To Shock A Hot Tub.

3. Alkalinity Increaser, pH Decreaser, pH Increaser

One of the most confusing elements of hot tub water chemistry is pH and total alkalinity. pH measures how acidic your water is. And alkalinity acts as a buffer for pH, neutralizing incoming acid and keeping your pH from drastically changing. These two go hand-and-hand and affect each other whenever they change.

Your total alkalinity levels should be between 100 and 150 ppm. And the proper level for pH is between 7.4 to 7.6. Low pH can cause corrosion in your spa. And high pH can cause itchy, dry skin and burning eyes.

There are a lot of products out there designed to raise or lower both pH and alkalinity all at once. But it’s important to have chemicals on hand that do one thing at a time.

• Alkalinity increaser: If your water’s total alkalinity dips too low, it can also bring your pH levels down. That’s why it’s important to have an alkalinity increaser on hand.
• pH decreaser (pH Down): But what if the alkalinity gets too high? Well, there’s actually no product called alkalinity decreaser. To lower your alkalinity, you’ll need to use a pH decreaser. And a pH decreaser obviously lowers pH, too. If your pH is too high, it can reduce your sanitizer’s effectiveness and cause cloudy hot tub water.
• pH increaser (pH Up): If your pH is too low, it could cause burning eyes and corrode parts in your hot tub. That’s when you’ll need to use a pH increaser.

Because this part of water chemistry can feel so complex, we have an entire guide on How to Balance Hot Tub pH (and with it, alkalinity).

4. Calcium Hardness Increaser

If you live somewhere with hard water, you may get calcium deposits on faucets and showerheads. But you actually want some of that hard water in your hot tub. If your hot tub water is too soft, it can eat away at your hot tub shell, pipes, and other parts. That’s why a calcium hardness increaser is so helpful.

Your calcium hardness levels should be between 175 and 250 ppm. Unfortunately, if your calcium hardness levels are too high, the best solution is to drain your hot tub, scrub it, and start over with fresh, filtered water. That’s why it’s important to add calcium hardness increaser a little at a time.

5. Line Flush Cleaner

Over time, the plumbing inside your hot tub can begin to accumulate mineral deposits, dirt, and grime. The only way to get rid of that build-up is to use a line flush cleaner and then drain your hot tub.

You’ll want to flush the plumbing and drain your spa every 3-4 months. And if you’ve never done that before, be sure to check out our complete walkthrough on how to drain and clean your hot tub.

We also make our own hot tub line flush cleaner at Swim University. You can check that out here:

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Optional Chemicals

• Hot Tub Water Clarifier: A water clarifier helps keep your water sparkling clear. Your hot tub water will look, smell, and feel cleaner when you use a clarifier once a week. Just keep in mind that a water clarifier treats the symptom, not the cause of cloudy water. If you don’t address the root of the problem, like low sanitizer levels or high pH, your water will go back to how it was once the clarifier wears off.
• Metal Sequestrant or Stain and Scale Preventer: If your water source has metals like iron and copper, you may end up with rust-colored or green stains in your hot tub. You can prevent them from occurring by using a metal sequestrant (also called a metal remover). If you have a mineral sanitizer, you’ll have to use metal sequestrant sparingly. Copper is often one of the active ingredients in mineral sanitizers. And too much sequestrant can possibly make the mineral sanitizer less effective.
• Hot Tub Filter Cleaner: You’ll need to remove and clean your filters every week if you have heavy hot tub use. You can use a filter cleaner or phosphate-free dishwashing detergent granules.
• Hot Tub Enzymes: Enzymes help break down organic contaminants like skin cells, body oils, and leaves. They’re not really necessary as long as you keep your sanitizer level balanced, and you drain, clean, and refill your hot tub every quarter.

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How To Add Chemicals To Hot Tub Water

Adding the right chemicals in the right order can prevent cloudy water, slimy surfaces, and nasty hot tub smells. And if it’s the first time you’re starting up your hot tub, it’s extra important to add them in the correct sequence. Luckily, all the chemicals you need to start up your hot tub are the same ones we mentioned before that you need to maintain your spa throughout the year.

You can watch this video tutorial or keep reading for the step-by-step guide on how to add chemicals:

Before you start adding any chemicals to your spa, you’ll want to know how many gallons your hot tub holds. This will help you add the correct amount of chemicals to your hot tub. You can find your hot tub’s volume or water capacity in your owner’s manual or with a quick Google search.

Here’s how you’ll be adding chemicals to your water:

• Add chemicals directly to your hot tub water. Measure out your chemicals, then add them one at a time to the surface of your hot tub water.
• Wait at least 20 minutes before adding the next chemical. Keep your jets running and your air valves off to help your chemicals evenly and quickly disperse. You’ll want to make sure each chemical is completely dissolved before adding the next one.
• Keep your cover off. You’ll want your hot tub cover removed so chemicals like chlorine can “off-gas.”
• Be safe. Use gloves, goggles, and a mask when handling chemicals. And keep your chemicals separate before adding them to your tub. Mixing chemicals outside of your water can be dangerous and less effective.

What Order Do You Add Hot Tub Chemicals?

Before adding chemicals, test your water. If this is your very first time filling up your hot tub, you may want to use a more comprehensive test kit to measure calcium hardness or metals like iron and copper.

Tip: Filling up your hot tub with a hose filter can help remove impurities like metals and calcium before they get into your spa.

Next, heat up your spa until the water temperature reaches 80 degrees Fahrenheit or 30 degrees celsius. The hot water will disperse your chemicals more effectively. And run your jets, turn off air valves and keep your cover off of your hot tub.

Finally, it’s time to add your chemicals one at a time, waiting at least 20 minutes between each chemical before retesting. Here’s the step-by-step sequence we recommend for adding chemicals to your hot tub:

1. Add metal sequestrant or stain preventer if necessary

If you need to add this to your water, do so before adding any other chemicals. This neutralizes metals in the water before they can stain your hot tub or harm your equipment.

2. Adjust alkalinity and pH

Your pH helps your sanitizer work more effectively. And Alkalinity helps prevent fluctuations in pH, so it’s important to adjust this level first. Alkalinity and pH go hand-in-hand, so adjusting one can affect the other. That’s why it’s important to add your chemicals one at a time, wait for them to dissolve, then retest your water. And remember, you can always add more, so don’t overdo it. Start with a few tablespoons if your levels are only a bit off.

• Both pH and alkalinity are low: Add alkalinity increaser first. Then test the pH again to see if it needs a pH increaser.
• Low pH: Add a pH increaser. If your pH is too high, add a pH decreaser.
• Low alkalinity: Add an alkalinity increaser.
• Either pH or alkalinity are high: Use pH decreaser to drop them back to the right level.

And after adding each chemical, let them circulate for at least 20 minutes, then retest your water.

#3. Adjust sanitizer levels, like chlorine or bromine

Now’s the time to add your chlorine granules or liquid bromine directly to the water. You can also use bromine tablets in a floating dispenser system. As always, start with a smaller amount of sanitizer, test your water, and add more if necessary.

Bromine does not dissolve as quickly as chlorine, so you’ll need to wait a bit longer to retest these levels. And if you’re using bromine tablets in a floater, this can take several days to disperse in your water before you get a proper reading.

If you’re using chlorine to sanitize your hot tub, we recommend using dichlor granules over trichlor tablets. It’s easier to control your dosing with granules compared to tablets. And trichlor can damage your hot tub’s acrylic shell.

4. Adjust calcium hardness levels

These levels do more damage in the long run, like eroding parts in your hot tub parts, so you can wait until your water is sanitized and balanced before adjusting your calcium hardness. Your calcium hardness levels should be between 175 and 250 ppm.

If you need to raise your levels, add a calcium hardness increaser. If your calcium hardness levels are too high, the best solution is to drain your hot tub, scrub it, and start over with fresh, filtered water.

Do You Need to Add Shock after Filling a Hot Tub?

You actually don’t need to add any spa shock right at this stage. Shock helps kill contaminants and remove compounds that build up over time, like chloramines or bromamines. Because your hot tub is full of fresh water, and you don’t have any build-up of contaminants, you don’t need to add shock right away.

You can add a non-chlorine shock once a week when your hot tub is in use. This will help refresh your sanitizer levels. You can also use a chlorine shock if you’re experiencing issues with your hot tub water, like cloudy water or algae, or if your hot tub is in high use.

Frequently Asked Questions About Hot Tub Chemicals

Looking for more help adding chemicals to your hot tub? Here are some common questions and answers.

Can you go in a hot tub without chemicals?

It’s not safe to soak in a hot tub without chemicals. That’s like getting into a bathtub after someone else has used it!  A hot tub without chemicals is the perfect breeding environment for bacteria, algae, and contaminants. Just like a swimming pool, you’ll need to keep your spa water sanitized and balanced. If you’re the very first person to get into a  freshly filled hot tub, you might be okay. But that water will get very nasty very quickly.

How soon can you use a hot tub after adding chemicals?

You’ll want to wait until your chemicals completely dissolve and your water levels are adjusted correctly before using your hot tub. This means waiting at least 20 minutes after adding chemicals before soaking in your hot tub. And if you’ve just added chlorine shock, you’ll need to wait even longer.

How often should you change the water in your hot tub?

You should drain and refill your hot tub every 3 to 4 months. This is the chance to remove biofilm and build up that gets stuck in your plumbing and can contaminate your water. Use a line flush cleaner and then drain, clean and refill your hot tub with fresh water.

Is chlorine or bromine better for sanitizing a hot tub?

Many spa owners choose bromine over chlorine. It can cost a little more, but it lasts longer in your water and is very effective at killing bacteria at high temperatures. You’ll also avoid that chlorine-like smell caused by chloramines.

Need More Hot Tub Maintenance Help?

• Download our free Hot Tub Cheat Sheet. It’s a free, easy-to-use guide to help you keep your hot tub clean and clear.
• Subscribe to our Swim University YouTube Channel. We publish free video tutorials about hot tub care.
• Check out our Hot Tub Video Course. You’ll get step-by-step videos and a downloadable guide with everything you need to know about hot tub maintenance.

The post Hot Tub Chemicals for Beginners: What You Need and How To Add Them appeared first on Swim University®.

Of course, chlorine immediately comes to mind. But have you heard of bromine? Even if you have, maybe you’re still not sure which sanitizer is right for you. And you’ll find chlorine and bromine tablets and granules are available, so which delivery method is best?

To make those decisions and keep your hot tub clear of icky hazards, you just need a little knowledge about both sanitizers, and how to add them to your spa.

Want to learn more about how to keep your hot tub balanced and sanitized? Then you should check out The Hot Tub Handbook and Video Course to help you save hundreds on chemicals and less time on hot tub maintenance all year long.

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Chlorine and Bromine, Tablets and Granules, Pros and Cons

While chlorine is the most common sanitizer for swimming pools, bromine is used to sanitize hot tubs more often, with good reason.

Before you can make an educated decision about which sanitizer to use in your hot tub, you need to learn about their features, benefits, and drawbacks.

How They Work

You know sanitizers kill bacteria and other yucky stuff. But exactly how do these two sanitizers do that?

Chlorine: It oxidizes contaminants, invading them and destroying them from the inside out. As it works, the chlorine dissipates and turns into a waste product called chloramines. These remnants are responsible for the stinging, drying, stinky reputation chlorine has, and reduce the sanitizer’s effectiveness.

To keep chloramines at bay, you’ll need to add chlorine on a regular basis, usually at least once a week. If it gets really bad, though, and the chlorine isn’t doing the job on its own, you can shock your hot tub to get rid of chloramines. You want to do that on a regular basis anyway, to keep your water clear and pristine.

Bromine: It ionizes contaminants, forcing apart their chemical bonds. A good amount of it remains active and working, even after combining with contaminants.

But bromine also produces a waste product called bromamines. While they’re not as noxious as chloramines, they still reduce the effectiveness of the bromine in your hot tub. Shocking is also the solution here.

Effectiveness

The measure of a sanitizer’s effectiveness is its reactivity rate. This refers to how quickly it destroys contaminants.

Chlorine: Kills contaminants more quickly than bromine does.

Bromine: Is a very reactive element, though not as reactive as chlorine, so it kills more slowly than chlorine.

Bromine also has a lower pH than chlorine, so it can help keep your overall water chemistry more balanced, which means less adjusting and finagling for you.

Stability

While chlorine may work more quickly, bromine is more stable than chlorine, especially in warm water.

Chlorine: Dissipates more quickly than bromine, and therefore needs to be replaced more often.

Bromine: Kills bacteria in your spa for a longer period of time than chlorine.

The exception to this rule is ultraviolet (UV) light, which destroys bromine more quickly than chlorine. This is a concern if you have an outdoor hot tub, and makes using your hot tub cover all the more important.

Even worse than red eyes and brittle hair is the debilitating effect chloramines have on a sanitizer’s ability to fight contaminants. The more chloramines in your hot tub, the higher the probability of algae growing and bacteria breeding.

Dosage Amounts

To get optimal benefit from any sanitizer, you need to use enough to work with how much water your hot tub holds, which correlates to how big the tub is.

The first thing to do is follow the manufacturer’s instructions. Then, to know whether you’ve used enough, you’ll need to test the water to gauge the levels.

Chlorine: The ideal level for chlorine is 1 parts per million (ppm) to 3 ppm, with 3 ppm being ideal.

Bromine: The ideal level for bromine is 3 ppm to 5 ppm, with 5 ppm being ideal.

If you end up with too much chlorine in your hot tub, you can try a few things to lower the levels. You don’t have to completely start over with fresh water. Same goes for bromine.

Also be aware that you’ll likely need to use a larger dose of bromine than chlorine to achieve the same sanitizing results, and bromine costs more than chlorine. But because you don’t have to use it as often, it’s possible that the cost may turn out to be the same. That also depends on the size of your hot tub, and how well you keep the water clean and balanced.

You’ll have to weigh the benefits against the cost to determine whether it’s worth the extra expense for you.

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Your Health

The spa chemicals you use are all safe in the proper amounts. But some people may react differently to them.

Chlorine: Can be harsh on the skin, hair, and eyes, especially at too-high levels.

Also, when chloramines linger in the humid air around a spa, they can cause breathing difficulty and even trigger asthma attacks.

Bromine: Is gentler on your skin than chlorine, but can be a bit more difficult to wash off after a long soak.

If you or anyone who uses your hot tub on a regular basis has sensitive skin or any kind of upper respiratory difficulties, bromine will likely be the better choice.

Safety

Whether you choose chlorine or bromine, DO NOT:

• mix them together in the water. This can also cause a dangerous chemical reaction. If you’re going to switch from one to the other, you’ll need to drain and clean your hot tub, and do a line flush.
• mix them together in their dry state, especially the granule forms. This can also cause a dangerous chemical reaction.
• store them next to each other. Even in their separate containers, this is dangerous as the fumes they give off can combine and become combustible.
• use the same feeder for both, whether you use chlorine or bromine tablets or granules. Even if you think you’ve cleaned it well enough, some of the chemical remnants can react with each other.

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How to Use Chlorine and Bromine Granules

If you know how to use a measuring cup, you can add chlorine granules or bromine granules to your hot tub.

1. Determine your hot tub volume, or how much water it holds.
2. Turn the hot tub on, if it isn’t already running.
3. Read the instructions on the chlorine or bromine container carefully.
4. Measure the amount of chlorine or bromine recommended by the manufacturer for your hot tub’s volume.
5. Pour the granules slowly and directly into the hot tub.
6. Allow the water to circulate for 20 minutes to allow the sanitizer to disperse.
7. Test the water to ensure proper sanitizer levels. Make adjustments as necessary.

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How to Use Chlorine and Bromine Tablets

You don’t have to add these as often as granules, but tablets are still not completely a set-it-and-forget-it method.

1. Read the instructions on the chlorine or bromine tablets container carefully.
2. Place the recommended number of tablets (usually 1-inch tablets) into a feeder (also called a floater, chlorine/bromine float, chlorine/bromine dispenser, chlorinator, or brominator).
3. Adjust the feeder (if it’s adjustable) according to the manufacturer directions to control the release of sanitizer.
4. Hold the feeder under the hot tub water for a few seconds to push the air out and keep it more stable while it floats.
5. Test the water over the next couple of days to ensure proper sanitizer levels. Make adjustments as necessary.

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Keepin’ it Clean

Remember that no matter how well you maintain sanitizer levels, you’ll still have to drain and clean your hot tub from time to time, ideally quarterly.

Change Your Mind, Change Your Sanitizer

The choice between chlorine and bromine tablets and granules should be a lot easier now. And remember you’ll be changing your water and deep cleaning your hot tub every few months. If you don’t like the sanitizer you chose, you can always switch when you change your water.

Whichever sanitizer you choose, just remember to regularly test to make sure the levels stay where they need to be to keep your water clean, and keep you and your hot tub guests healthy and happy.

Happy Soaking!

The post Chlorine Versus Bromine: Choose The Right Hot Tub Sanitizer appeared first on Swim University®.

Despite the many things that can deplete sanitizer in your spa, every now and then, you may find yourself with too much chlorine in your hot tub, or too much bromine, if that’s what you use. You’re risking corrosion of your hot tub components, deterioration of your headrests and spa cover, and even skin rashes if you don’t lower sanitizer levels quickly enough.

Want to learn more about how to keep your hot tub balanced and sanitized? Then you should check out The Hot Tub Handbook and Video Course to help you save hundreds on chemicals and less time on hot tub maintenance all year long.

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What Are Chlorine and Bromine?

Chemical balance is vital in your spa because healthy water keeps you safe and prolongs the life of your hot tub. Chlorine and bromine are sanitizing agents used to keep your water safe and sanitary. They’re a necessary part of proper hot tub water care because they destroy dangerous contaminants in your spa.

Though it may seem unnecessary—or even wasteful if you’re a hot tub newbie—frequent sanitizer doses are integral to your water’s cleanliness and safety. You’ll find yourself testing for and adding chlorine or bromine to your spa even more frequently than you would a pool.

The relatively small volume of hot water in a spa is a perfect breeding ground for bacteria such as legionella, which can cause Legionnaires’ disease.

Since you’re here to find out how to lower your sanitizer levels, chances are you’ve already chosen which sanitizer works best for you. And if you haven’t the chlorine versus bromine question really comes down to your preference.

Chlorine oxidizes spa water contaminants and bromine ionizes them, so your filtration system can get rid of them. Both do a good job when used properly.

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Are You Sure It’s Too Much Chlorine In Your Hot Tub?

Have you been noticing a strong chemical smell around your hot tub? Maybe you or other bathers have experienced stinging eyes or irritation in your throats and noses. Surely this means you overdid it with the chlorine? Well, not necessarily.

These are common signs of chloramines or bromamines, the noxious chemicals left behind after your sanitizers attack contaminants. The presence of chloramines or bromamines typically signals that you need to shock your hot tub. In other words, you need to add more sanitizer, not less.

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High Sanitizer Indications

If your sanitizer is out of control or stays at a high level for a long period of time, your hot tub surfaces may start to degrade. Damage (and sometimes buildup) on the underside of your spa cover, headrests, and other soft surfaces can occur fairly quickly when sanitizer levels are high.

Your filter may also break down more quickly. You might notice worsening dry skin and brittle hair after soaking with too much chlorine in your hot tub. (By the way, you may want to try swimmer’s lotion and chlorine removal shampoo to alleviate dry skin and hair caused by exposure to high chlorine or bromine levels.)

But the most reliable way to determine whether you’ve got too much chlorine or bromine in your hot tub is to test your hot tub water. You can also take a sample to your local pool store for professional testing.

Either of these testing methods will help you determine whether you really have a sanitizer problem or some other water chemistry issue.

When you test your water, what you really want to know is how much functioning sanitizer is in your water. In other words, how much of the chlorine or bromine in your water is still killing bacteria and contaminants. This is known as free chlorine. The used up portion is combined chlorine. When you add free and combined chlorine together, you get total chlorine.

You can replace chlorine with bromine in every instance, and the same applies.

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How Much Sanitizer You Actually Need

Ideal sanitizer levels are a cornerstone of basic hot tub chemistry. If you use chlorine in your hot tub, you’ll want to maintain 1 part per million (ppm) to 3 ppm, with 3 ppm being ideal. If you use bromine, keep it between 3 ppm and 5 ppm, with 5 ppm being ideal.

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How to Lower Your Hot Tub Chlorine or Bromine

You know the ideal concentration levels for sanitizer, you’ve tested your water, and sure enough, you’ve got too much sanitizer floating around.

What’s next? You’re in luck. Bringing down your bromine or chlorine levels may be one of the simplest problems to fix in your spa.

Step One: Do Nothing

We’re not kidding you. If your sanitizer levels are a little bit high, you could opt to not do anything at all

Don’t add any more doses of chlorine or bromine to your hot tub. If you have a chlorinator or other device that slowly, constantly adds sanitizer, turn it off or remove it from your spa.

Step Two: Do More Nothing

Yep. Just sit on your hands and give it a day or two. The sanitizer levels will naturally decrease, and probably pretty quickly. Just know that you probably want to stay out of the hot tub during this time.

After a couple of days, test your water again. If the sanitizer levels are still high, it’s time to take action.

Step Three: Open Your Hot Tub

Completely remove your spa cover. This allows significantly more water (and by extension, chlorine or bromine) to evaporate.

This step is a bit of a twofer. It will lower chlorine or bromine levels in your hot tub, plus decrease your water level so you can move on to the next action.

Step Four: Dilute Your Water

The water level will likely have dropped a couple of inches, and you can simply top off your spa with fresh, clean water. Let it circulate, then test it again.

But if you didn’t lose much through evaporation, and your spa is still nearly full, you’ll need to remove some water so you can reduce the concentration of sanitizer with fresh water. This will be enough to lower the bromine or chlorine to the desired level in most situations.

If your spa water has been in your hot tub for two or three months, it’s about time to drain and clean your hot tub anyway. Also, if your water chemistry has been difficult to balance aside from high sanitizer levels, that’s another indication that it’s time to drain and clean.

In either case, it makes more sense to start with a full load of fresh water than trying to top off old or highly unstable water.

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When You Can’t Wait for it to Evaporate

You need to use your hot tub as soon as possible, so you don’t have time to take off your hot tub cover and wait a few days for your sanitizer to dissipate. No problem. You can use a hot tub water additive called neutralizer, which literally neutralizes chlorine and bromine.

Its chemical name is sodium thiosulphate and it’s so effective at getting bromine and chlorine out of water that scientists use it to remove chlorine from water samples before testing and doing, you know, science stuff.

Important: We recommend using neutralizer only if you’re in a pinch. It’s easy to use too much, leaving your hot tub without enough working sanitizer. Neutralizer will continue to destroy chlorine or bromine until the neutralizer is completely used up. While it’s great that it doesn’t linger in your water indefinitely, you could find yourself swapping too much sanitizer for not enough sanitizer. If you do take the neutralizer route, follow the manufacturer’s dosing instructions carefully, and remember that it’s only a temporary solution.

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Practice Good Water Care To Prevent Future Problems

We can’t stress it enough: creating and sticking to a water care plan for your hot tub is the single most important thing you can do to keep your spa—and all the people who enjoy it—healthy.

Follow water care best practices, and you’ll prevent many potential chemistry issues.

Daily: Run your filter twice per day, for at least an hour each time. If you’re using your hot tub that day, you can run it longer to better filter out human-introduced contaminants.

You may also add a dose of sanitizer or spa shock after each use, if you wish. Check your hot tub manual for your manufacturer’s recommendations.

Weekly: Pull your filter out and rinse it thoroughly with clean water, or use a filter cleaner, if necessary. Test your water, then adjust alkalinity, pH, sanitizer, and calcium chloride as needed.

If you’ve added sanitizer during the week, you may not need to add a weekly dose, so always be sure to test before adding anything.

Every Three to Four Months: Just about quarterly (and any time you experience a serious water chemistry problem, like an algae bloom) flush your hot tub circulation lines and jets with a line flush product to eliminate biofilm.

After the sludge and bacteria in your lines is dead and circulating, completely drain the dirty water out of your spa. Clean your hot tub, wash or replace your filter cartridges, then refill your spa with fresh water. Consider using a hose filter to prevent metals and other contaminants from entering your spa in the first place.

After you refill your hot tub, balance the water chemistry and shock it. Be sure to test the water one last time before stepping into it the first time. This will ensure your spa contains the correct amount of sanitizer to destroy contaminants quickly so you won’t be soaking in your own germs—or worse, someone else’s. Ew.

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Too Much Sanitizer Is Not a Good Thing

Moderation is the key when adding any chemicals to your hot tub. Everything you pour in affects something else. They all have the potential to harm you or your spa and components if your chemistry isn’t balanced.

So if you find you have too much bromine or chlorine in your hot tub, don’t worry! You can avoid complications by taking the simple steps to bring it down to healthy levels as soon as possible. You’ll be back to enjoying your spa in no time.

Happy Soaking!

The post How to Lower Bromine or Chlorine Levels in a Hot Tub appeared first on Swim University®.

But the most unshocking reason to use spa shock? It’s just smart. That water remains in your hot tub for weeks or months at a time. Don’t you want to make sure it’s always completely clean and sanitary? Of course you do. Which is why you must learn how to shock your hot tub.

What is Spa Shock?

First, let’s be clear—this has nothing to do with electricity. That definitely doesn’t mix with water.

Hot tub shock is a large dose of oxidizer used to “shock” the water into a clean state after it’s been contaminated somehow. It performs three main functions.

It Removes Organic Contaminants

Every time you get into your hot tub, you take all kinds of organic contaminants in with you. Shampoo, lotion, makeup, sunscreen, hair, dead skin cells, and remnants of whatever else your body has come into contact with that day.

And if more than one person is using your hot tub on a regular basis? Multiply all those contaminants by the number of people soaking in the water and … that’s math you don’t really want to do.

You can reduce the amount of organic contaminants by showering—or at least rinsing off—before every soak. But that’ll only go so far. The remaining yucky stuff will be attacked by your sanitizer. But that also only goes so far.

After a while, your sanitizer gives out, and those contaminants build up in the water and create problems like hot tub scum or cloudy hot tub water. Blech.

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It Kills Bacteria

There’s regular bacteria that’s just gross and sometimes causes discoloration on things like your shower curtain. That pinkish stuff? It’s not rust. It’s bacteria. Wash your shower curtain with bleach to get rid of it.

And then there’s the really nasty bacteria that causes illness. Hot tubs are known for being incubators for three specific types of illness-causing bacteria:

• Pseudomonas Dermatitis: causes hot tub folliculitis
• Legionella: causes Legionnaires’ disease, a severe type of pneumonia
• non-tuberculous mycobacteria: causes hot tub lung, a granulomatous (chronically inflamed tissue) lung disease.

These and all other bacteria can be kept at bay by keeping your hot tub water balanced and ensuring that sanitizer levels in particular remain steady. But in between water tests and chemical additions, sanitizer is used up to keep the water clean.

Spa shock will give it a boost and kill anything that might’ve been cropping up in the water before it has a chance to make anyone sick.

It Removes Chloramines or Bromamines

You know that “chlorine smell” you associate with public pools and hotel hot tubs? It’s not the chlorine that smells; it’s the chloramines.

As chlorine is used up killing bacteria and removing organic contaminants, it produces waste products. Those are chloramines, they’re what you smell. They’re also what you’re breathing in until you get the sanitizer level back where it needs to be.

Hot tub shock brings that level up quickly, and eradicates chloramines from the water, getting rid of the smell, and allowing you to breathe easier.

If you use bromine as your sanitizer, it also produces waste products called bromamines. They’re not as noxious as chloramines, and you may not even notice them. But they’re still not something you want to breathe in. Keep the bromine level steady, and shock regularly.

So you see why shocking your hot tub is an essential part of caring for it. But not all shocks are created equal. Some types eradicate all contaminants, while others only work on a few.

Our Top Pick

SpaGuard Chlorinating Concentrate

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Hot Tub Shock Types

You’ll find four main types of spa shock available. But only two of them are viable for hot tubs.

Calcium Hypochlorite

Also known as cal hypo, it’s inexpensive and convenient because it’s widely available. But you should not use it to shock your hot tub. It’s better for pools.

Cal hypo is unstabilized chlorine, which means it’ll lose about 95% of its effectiveness after just a few hours of heat exposure in your hot tub. It also contains calcium, and in a small body of water like the one in your spa, it will quickly deposit scale on surfaces and components, potentially damaging them.

Important: Only use chemicals labeled specifically for use in hot tubs. It’s a smaller body of water, and it’s heated to much higher temperatures than pools, which means chemicals that work fine in pools will react differently in spas. Prevent damage—and voiding your manufacturer’s warranty—by only using spa chemicals.

Dichlor

Technically named sodium dichloro-s-triazinetrione or dichloroisocyanuric acid, it’s a lot easier to call it dichlor shock. It’s the active ingredient in most brands of hot tub shock.

You can usually add it directly to the water without dissolving it first, but always follow the manufacturer’s instructions on the package.

As you can tell from that second scientific name, it contains a small amount of cyanuric acid, which means it’s stabilized, which means it will stand up to the spa’s heat. Still, keep a close eye on your sanitizer level, and if your hot tub is outside and not under any structure like a gazebo, shock it at dusk or night to keep the sun’s rays from eating the chlorine away too quickly.

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Lithium Hypochlorite

You may see this type of shock at your local hot tub or pool supply store. But we doubt it. Lithium hypochlorite isn’t as widely available as it used to be because most lithium is now used to make lithium batteries. This also means the cost of the raw material has gone up a lot, making the shock (if you find it) more expensive than it used to be, too.

Do yourself a favor, and stick with dichlor shock. It’s less expensive, and you can find it anywhere.

Non-Chlorine Shock

The most important thing to know about non-chlorine spa shock is that it is not a disinfectant. This means it does not kill bacteria. So why even use it?

Well, its most common active ingredient, potassium peroxymonosulfate, is an effective oxidizer. Used weekly, it does a great job of getting rid of organic contaminants (skin cells, lotions, etc.), and clearing the water if it’s become a little cloudy due to those contaminants.

Also, if you use chlorine as a sanitizer, it activates free chlorine, the type of chlorine needed to kill bacteria. It does the same thing for bromine.

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Which Spa Shock Should I Use?

Well, that depends on which sanitizer you use.

Chlorine

Use chlorine shock. This one’s a no-brainer, right?. But you can also use non-chlorine shock more frequently to address organic contaminants and keep the water clear between regular chlorine shocks.

If you do that, test often and keep an eye on the chlorine level to make sure it doesn’t drop below 1 ppm. You actually want to keep that at 3 ppm, the higher end of the recommended range.

But if you use your hot tub often, or you have a high bather load (several people use it), we highly recommend sticking with chlorine spa shock to kill bacteria and keep the water sanitary.

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Bromine

Use chlorine shock. But, just as with chlorine, you can also use non-chlorine shock for all the same reasons.

Again, we recommend sticking with chlorine shock if you have a high bather load.

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Biguanide

Use biguanide shock. It’s actually hydrogen peroxide, but not the kind you keep in your medicine cabinet, so don’t think you can just pour in a bottle of that cheap stuff from the drugstore and be good to go.

Manufacturers that make biguanide sanitizer usually have a whole line of products (oxidizer, water clarifier, test strips) made to work with biguanide.

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Minerals

Use non-chlorine shock. If you’re using a spa mineral sanitizer, you already know you have to supplement with a little chlorine to get the full sanitizing effect. But that chlorine level should only be 0.5 ppm, so if you used chlorine shock, you’d likely end up with too much chlorine in the water.

This isn’t to say you can’t ever use chlorine shock. If you’re having a problem with bacteria, algae, or the chlorine level is at zero, chlorine spa shock is the way to go.

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Salt Water

Use chlorine shock. The salt chlorine generator is turning salt into chlorine, which is what’s sanitizing your spa. This makes chlorine shock the best choice.

You can also use non-chlorine shock if you’re concerned about the chlorine level being too high.

Ultraviolet, Ionizer, or Ozonator

Use chlorine shock. Dichlor is compatible with these systems, but always follow the manufacturer’s instructions.

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01/27/2023 09:00 pm GMT

The Best Way to Shock Your Hot Tub

If you’ve never learned how to shock a hot tub, it’s not a complicated process. But you do need to take a few precautions and follow the steps in a certain order to get the most benefit from spa shock.

You’ll need:

• hot tub shock (whichever type is recommended for the sanitizer you use)
• chemical-resistant measuring cup
• test strips
• chemical-resistant gloves
• safety goggles

Once you have your supplies gathered, you can get to work.

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Uncover Your Hot Tub

And leave it uncovered throughout this process. Once you add the shock, some of it needs to off-gas—dissipate—from the water.

This also applies to the floating thermal blanket (if you have one), and any accessories that may be floating in the water.

Important: Do we really need to say that no one should be in the hot tub when you add spa shock to it? Or when you add any chemicals to it? We’re gonna say it anyway, for the people in the back.

Test the Water

Before shocking your spa, the pH must be at the correct level, between 7.4 and 7.6. High or low pH in your hot tub will affect the shock’s ability to work as well as it should.

If it’s not in the right range already, adjust it, then continue with shocking.

Turn Off the Blower

The circulation pump needs to remain on to distribute the shock through the hot tub. But turn off the jets so the water is moving but not too agitated, and to prevent the spa shock from off-gassing too quickly.

Put On Your Safety Gear

Shock (and every other chemical you put in your hot tub) is, well, a chemical. You don’t really want it on your skin, and you definitely don’t want it in your eyes.

In addition to gloves and safety goggles, consider wearing long pants, a long-sleeved shirt, and closed-toe shoes.

If your hot tub is inside, open a window, turn on an exhaust fan, or both. However you do it, make sure there’s good ventilation in the room before you open and use any chemicals.

If your hot tub is outside, try to shock it when it’s not windy. If there’s a breeze, stand upwind from the hot tub, and keep your hands as close to the water’s surface as possible to prevent chemicals from blowing anywhere but into the hot tub.

Important: If you spill any shock, clean it up immediately and dispose of it safely. Always keep spa shock (and all other chemicals) out of the reach of children and pets at all times.

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01/27/2023 04:08 pm GMT

Measure the Shock

You’ll never just pour shock into the spa directly from its container. Eyeballing it is not an option. Measure the amount of shock you need for the amount of water your hot tub holds. Check the shock’s label to find this information.

And if you’re not sure how many gallons of water are in your hot tub, consult the manufacturer.

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Shock It!

Carefully add the shock to your hot tub using the method prescribed by the shock’s manufacturer.

Leave the Hot Tub Uncovered

Don’t cover the spa for at least 20 minutes to allow the spa shock to disperse and dissipate.

If you’re not going to use the hot tub immediately after shocking, do put the cover on after 20 minutes to prevent evaporation.

A Few Shocking Questions

Now that you know how to shock a hot tub, you probably still have a few questions. Well, we’ve got answers.

How Long Before I Can Use the Hot Tub Again?

There’s no hard and fast rule about when you can get into your hot tub after you’ve shocked it. It’s going to depend on when the sanitizer level has dropped back down to where it’s supposed to be.

The only way you’re going to know that’s happened is by testing the water. But also check the shock manufacturer’s instructions for any special considerations.

How Often Should I Shock My Hot Tub?

Easy question with a simple answer: weekly. Actually, the answer is at least weekly. If your hot tub gets a lot of use, or you have a lot of people in it at once—or both—you may want to up that to twice a week.

Just remember to always test the water before you shock to make sure the pH is where it needs to be, and before you get back into the spa to make sure the sanitizer is where it needs to be.

When Should I Shock My Hot Tub?

If it’s indoors, anytime is fine. If it’s outside, and it’s not underneath a structure like a patio cover, wait until dusk or night.

Even if you’re using dichlor, which does contain some stabilizer, it’s best to prevent the sun’s rays from burning off the chlorine before it has a chance to work.

Shocked by How Easy That Was?

Now you know how to shock a spa! Which also means now you have no excuse to skip it. But trust us, even if maintaining your hot tub is a royal pain sometimes, you’ll be glad you did when you can soak in clean, sanitary water with no worries about nasty stuff like algae or bacteria.

Remember, always read the manufacturer’s instructions before you begin. Preventing a chemical mishap is much better than possibly have to drain your hot tub and start over.

Happy Soaking!

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