Hot tubs should be clean, steamy, and inviting. But if you don’t take care of them, they can quickly become a haven for nasty bacteria and algae.
The most important thing you can do to make sure your hot tub is ready for use at all times is to frequently check the chemicals.
Make sure your pH, sanitizer, alkalinity, and calcium hardness levels are all within normal range a couple of times a week.
During these checks, you’ll often have to add a little something to balance the chemistry, so it’s important to know what to use. And since not all chemicals are the same, here’s a guide to help you pick the ones you need.
The 10 Best Hot Tub Chemicals
#1. Leisure Time Bright & Clear
- BENEFITS: Helps spa filters perform at peak efficiency; prevents scale formation
Leisure Time Bright and Clear usually makes the top of everyone’s favorite spa chemical list. It’s designed specifically for hot water use and is compatible with all types of sanitizers.
This chemical suspends contaminants, clumping them together so that they can easily be trapped in the filter and removed. This action helps maximize your filter’s performance, keeping your hot tub water clean and clear.
#2. Leisure Time Renew Non-Chlorine Shock
- Quickly dissolves in water to rid spa water of oils and residue
Shocking your hot tub is an important part of maintenance to keep your water clean and safe. This is especially true if you want to keep from having to drain it very often.
It’s also a great chlorine booster to sort of rev up its effectiveness between applications.
Leisure Time Renew is a non-chlorine shock treatment that uses oxidation to clean and deodorize your water. This means it can be used with all types of sanitizers, including chlorine, bomine, ozone, and mineral systems.
#3. Clorox XtraBlue
- Quick-dissolving, dual action pool chlorine granules that maintains a healthy pool
When you own a hot tub, you have to choose some type of sanitizing system. This can be chlorine, bromine, salt, ozone, or mineral.
Chlorine is the top pick because it’s the most effective and usually the cheapest. But you do have a choice when it comes to the type of chlorine you use.
Clorox is a trusted name in cleaning and their chemicals for hot tubs are no exception. This particular product is a 6 in 1 formula designed to sanitize, shock, treat algae, remove contaminants, and reduce eye irritation.
It also contains an agent that buffers itself against UV rays so it lasts longer than other chlorine products.
#4. Leisure Time Chlorinating Granules
- Specifically formulated for spa and hot tubs
Leisure Time Chlorinating Granules is another chlorine product perfect for hot tubs. This formulation is about as pure as you can get, so you can use it with any of your other preferred chemicals.
Chlorine for hot tubs basically comes in two types of materials — liquid or granular. Liquid chlorine has a tendency to spill and splash, but granular is much easier to control.
#5. SpaGuard Enhanced Spa Shock
- SpaGuard Enhanced Shock (6 lb)
SpaGuard Enhanced Shock is a great product to boost and super-chlorinate your pool. It removes contaminants and unpleasant odors, restoring your water to the clean, clear liquid you started with.
The great thing about this product is that you can return to soaking in as little as 15 minutes after treatment. And it’s compatible with any type of sanitizing system.
#6. SpaChoice Sanitizing Granules
- Dissolves Quickly and Completely
This chlorine chemical is granulated for easier use. It’s also extremely pure so it can be used as both a daily treatment and shock.
It is stabilized so it won’t break down as quickly, even with constant sun exposure. And it dissolves very quickly, making it safe to swim in soon after application.
#7. Spa Essentials Brominating Tablets
- Spa Essentials Brominating Tablets are a spa and hot tub sanitizer
Some people choose to sanitize their hot tubs with bromine rather than chlorine. If you do, this is the one we recommend.
Spa Essentials Brominating Tablets are compressed 1” tablets that you put directly into your floater or feeder for long-lasting effectiveness.
These are easy to use since they come pre-measured and are a good alternative if you simply can’t stand the smell of chlorine.
#8. Frog Ease Floating Sanitizing System
If you want a sanitizer that’s simple to use, this system is as easy as they come. Frog Ease comes in a little floater that you simply toss in the water.
There’s no guesswork with this system as the floater just flips itself over whenever it’s time to replace it.
The chemicals in it are both minerals and SmartChlor technology. This means it kills bacteria with a lot less chlorine than other systems, so the water is a little softer.
#9. Clorox Pool & Spa All-in-One
Clorox All-in-One is designed to both treat and shock your hot tub whenever needed. It’s almost 100% pure chlorine so it will kill any and all contaminants it comes in contact with.
This is another stabilized chemical so it won’t break down with frequent UV exposure. And it comes in granular form so it’s easy to use and dissolves quickly.
#10. Zodiac Nature 2 Spa Stick
Zodiac spa sticks offer hot tub owners a good alternative to both bromine and chlorine sanitizers. It’s mineral-based and provides great sanitizing power without a lot of effort.
These sticks can simply be dropped into your spa filter for up to 6 months of cleaning power. This is a good alternative if you don’t like the strong smell of chlorine and bromine doesn’t do the trick.
Types of Hot Tub Chemicals
Hot tubs make a particularly cozy breeding ground for bacteria because of the warmer water temps. So they do require special care to keep them safe and clean.
You don’t necessarily have to use all of these, but here’s a rundown of the types of chemicals available:
Sanitizers: these are the main chemicals you will use to keep your hot tub free from bacteria. The most common are chlorine and bromine, but occasionally, you will see mineral or salt systems.
Shocks: Shock is also a sanitizer, but it’s usually used to super-chlorinate your water to get everything back in balance. Shocking is best done at least twice a month or when there have been any changes, such as refilling or high usage.
pH balancers: pH and alkalinity levels tend to rise a little too high in hot tub water, but occasionally, it might fall too low. pH reducers and increasers are chemicals you can buy to combat either problem.
Clarifiers: Cloudy water is usually due to microscopic contaminants too small to get filtered out. A clarifier will clump these particles together so that the filter can trap and remove them.
Specialty: This category holds a few chemicals that can’t be grouped into the main categories. One example is a foam reducer that is used when you have trouble with excess surface foam. Another is algaecide that is used when you need a little extra help getting rid of the green stuff.
Choosing the Best Hot Tub Chemicals: 3 Things to Consider
The amount of use your hot tub gets.
If you use your hot tub daily, you’ll probably have different chemical needs than someone who uses it once a month. For example, you may have to shock your tub more often, so you’ll need to keep pool shock on hand. Or you might have to buy a foam reducer since body and hair products tend to cause extra suds.
Your water supply.
Some areas of the world happen to have much harder water than others, meaning you might have more of a problem with calcium buildup. In these cases, you’ll have to keep a close eye on the calcium hardness when you check the water chemistry.
Since you’ll have to take particular care to balance the pH levels as often as you can, you’ll need to keep pH increasers and reducers on hand.
The ingredients in the chemicals.
Read the labels when you’re picking out your chemicals so you know exactly what you’re getting. For example, trichlor and calcium hypochlorite are popular chlorine for pools, but it’s not recommended for hot tubs. Instead, stick with sodium dichlor.
11 Hot Tub Chemical Terms to Know
Acrylic. Most hot tub shells are made out of a non-porous acrylic material. This is durable and easy to clean, but you need to be aware of it when you choose your chemicals.
Biofilm. Both pools and hot tubs are susceptible to this slimy film that accumulates in nooks, crannies, pipes, and pump lines. It holds on to unwanted bacteria and debris, making your water unhealthy. Clean your tub regularly to avoid this.
Bromine. One alternative sanitizer to chlorine. It’s a popular choice for people who wish to avoid that strong chemical smell in small spaces.
Defoamer. This chemical is used to reduce the foam on the surface of hot tub water that often accumulates because of soaps, oils, shampoos, and lotions.
Flow switch. Some hot tubs use these pressure switches that monitor water flow through the heater.
Jacuzzi. Jacuzzi is actually a brand of hot tubs that became popular a long time ago. Many people refer to spas as Jacuzzis, but this is actually inaccurate.
Ozonator. Some hot tubs use an ozonator to boost the effectiveness of the sanitizer. You still have to use chlorine or bromine with it, but this machine oxidizes the water and makes it purer.
pH reducer and pH increaser. These are 2 chemicals you need to keep on hand to keep your pH levels balanced.
Sodium Dichlor. Sodium dichlor is the only chlorine product recommended for hot tubs because it has a neutral pH and doesn’t need to be stabilized.
Trichlor. Trichlor is a popular chlorine product for swimming pools, but it’s not recommended for hot tubs because of its high acid content.
Cal-hypo. This is another chlorine product not suitable for hot tubs. This one will cause calcium buildup on spa plumbing and heating.
How to Balance the Sanitization Levels of Your Hot Tub
Keeping your hot tub clean and safe requires a lot more than just checking your sanitizer levels. All the other levels work together to make it effectively kill germs.
Step 1: Balance pH levels
Sanitizer works best with a perfect pH balance, which is between 7.2 and 7.8, according to the CDC. Most of the time, if this is out of balance, it will be too high and you’ll need to add some pH reducer.
But if it does get too low, you can also use a pH increaser.
Step 2: Balance alkalinity levels
Hot tub alkalinity should be between 80 and 120 ppm, and it goes hand in hand with pH balance. To raise or lower this, you will use the same chemicals as you would for pH balancing.
Step 3: Balance calcium hardness
If you live in an area with extremely hard or soft water, this will be more of an issue. If it falls below 100 ppm or above 250 ppm, it can cause serious equipment damage and become uncomfortable to bathe in.
The best way to avoid this is by filtering your water before you put it in the tub. You can buy hose filters fairly inexpensively that will filter out a lot of unnecessary junk.
But if you still happen to have hard water in your area, it’s a good idea to keep some scale controller on hand.
Step 4: Balance sanitizer
If you use chlorine, those levels should be between 1.0 and 3.0 ppm.
If you use bromine, the optimum levels are 3.0 – 5.0 ppm.
Usually, during your regular pool maintenance, these levels will be low because your water has depleted it, so you’ll just add some more.
But if it does happen to get too high, you may need to add water or shock your hot tub.
Hot Tub Chemical FAQs
Is chlorine or bromine better for hot tubs?
This is usually a matter of personal preference, but there are some pros and cons to both. For example, if the smell of chlorine can be overwhelming if your hot tub is kept in a small, enclosed space, so many people with indoor tubs choose bromine.
On the other hand, bromine is not stabilized, so sunlight depletes it very quickly. For this reason, chlorine is usually better for outdoor hot tubs.
How often should I shock my hot tub?
When your hot tub is being used regularly, it’s recommended that you shock it once a week during regular maintenance. But you can get by with doing it every two weeks during the months it doesn’t get much use.
How soon can you use a hot tub after adding chemicals?
This depends on the type of chemicals you’re using, but with most of them, you’re safe to enter the water after 15-20 minutes. Shock, though, is usually a different story. You may need to wait up to 24 hours.
Always follow the manufacturer’s recommendations to stay on the safe side.
Can you use a hot tub without chemicals?
A hot tub without any chemicals will quickly grow all types of bacteria and fungi that are unsafe for humans. But there are alternatives to traditional chemicals.
Saltwater systems, for example, use salt to sanitize the water. Many people prefer this method as it creates softer water and lighter odor.
Keeping your hot tub chemistry balanced is a crucial part of making sure the water is safe to bathe in and your equipment lasts as long as possible.
But keep in mind that pool chemicals are not always the best option for your smaller and warmer hot tub. Try to stick with products designed especially for spas and you likely won’t go wrong.