Hot Tub Chemicals

all about hot tub chemicals

Have a hot tub at home? Bet you love getting soaking in it! Or if you’re like me who looks forward to getting into the hot tub as soon as you reach home. Ahhh! Nothing to beat it when it comes to unwinding and relaxing.

But how well do you maintain your hot tubs? Have you given it any thought? Hot tubs are breeding grounds for bacteria, microbes and germs. Gross, right? But if you maintain them well, you don’t have to worry too much.

Hot tub treatment has to be done frequently to ensure that your spa water is safe, clean and hygienic. The chemicals with this you treat your hot tub water kill the potentially deadly bacteria and germs. Added to this, if your skin is sensitive, you may be wondering what are the best hot tub chemicals for sensitive skin.

There are 2 factors that you need to keep in mind when choosing chemicals for a hot tub.

  1. Chemicals that are gentle on your skin and are safe.
  2. Chemicals that treat the water in your spa keeping it clean, healthy and fresh.

So, if at this point you are thinking,

Chlorine or bromine?

Is chlorine even good for your skin?

What chemicals to use in a hot tub?

Any alternatives to chlorine and bromine?

Do you even need to use chemicals?

how to maintain hot tubs without chemicals?

I will try to answer all of these. Dive right in to find out!


Chlorine and Bromine

Chlorine and Bromine are the 2 main sanitizers used in Hot tubs. They keep the water in your hot tub balanced and safe for you to hop in. A sanitizer is probably the most important of all the chemicals that you will use in a hot tub. Chlorine is rather well-known. Bromine is a bit of a mystery to some. In either case, see how well you know about the 2 chemical sanitizers that go into your hot tub!


  • Dissolves Faster
  • Less expensive
  • Kills algae more quickly
  • Less stable in high temperatures
  • Chlorine can cause harm to eyes and skin
  • Shock treatments are needed more often
  • It gives off an unpleasant odour because it releases chloramines during oxidation of contaminants
  • Does Not last as long
  • It cannot take the heat as effectively as bromine
  • Proper Chlorine Level: 1 – 3 ppm


  • Dissolves slower
  • More expensive
  • Adept at killing bacteria and viruses
  • More stable
  • Less irritating to the skin and eyes
  • Shock treatments are needed less often than with chlorine
  • No odours here because bromine releases bromamines during ionization of contaminants, which are not as noxious as chloramines
  • Lasts longer than chlorine
  • It can take the heat of the hot water better than chlorine
  • Proper Bromine Level: 3 – 5 ppm

Unless your hot tub is prone to algae formation, bromine is the better and safer choice. It is better at killing the bacteria and viruses(common hot tub infestations) and doesn’t harm your eyes, hair or skin. Which brings us neatly to the point. Is chlorine good for the skin?

The short answer is No, as you would have gathered if you paid attention to the above comparison of chlorine and bromine. But why do you ask?

Well, the chlorine in the water will strip natural oils from your skin making it dry and sometimes, itchy. To make up for the loss, your sebaceous glands will overproduce sebum or oil, to restore the oils stripped away due to chlorine exposure. This overproduction may result in clogged pores and trigger breakouts if your skin is already prone to acne.

People with dry skin problems like eczema, psoriasis etc are more susceptible to the drying effects of chlorine. Another skin problem that can occur when you take a dip in chlorinated water is the development of rashes. If you regularly use chlorine in your water, have a care because it can cause rashes, itchiness and swollen skin as the skin begins to lose its natural balance.

pH Balancer

To ensure that the pH levels in your tub are well balanced, you should have a pH increaser and a pH decreaser. (Or a pH up and pH down). The former should be used if your pH is low and the latter when it is high.

But why even care? A pH will indicate how acidic or basic the water in your hot tub is. To be able to use the hot tub, the water should be neutral. A low pH can cause skin irritation and even damage your spa while a High pH can cause eye and skin irritation while making the sanitizer ineffective. So your spa water is exposed to contamination by bacteria, algae, germs, pathogens, diseases and…I could go on but I don’t want to gross you out too much. Just keep the pH levels in check okay?


And finally, but not so shockingly, shock! This is important to properly maintain your hot tub water. When you are about to use your hot tub after ages and if you are someone who uses your hot tub regularly, you need to shock your spa to keep the water safe and contaminant-free.

Shocks kill the bacteria and remove bromamines and chloramines from the water. The shocks will break the bonds of these contaminants from your hot tub. So you water after a “shock” is safe and healthy to use.

These are our roundup of the best chemicals for hot tubs.

  1. SpaGuard Enhanced Spa Shock
  2. SpaChoice Chlorine Granules for Hot Tubs, 5-Pounds
  3. Leisure Time Spa 56 Chlorinating Granules
  4. Leisure Time Spa Disinfectant Brom Tabs
  5. Oxy-Spa Oxidising Shock
  6. Leisure Time Bright and Clear
  7. SpaGuard Chlorinating Concentrate – 2 Pounds
  8. Clorox Pool & Spa 23006CLXCA

SpaGuard Enhanced Spa Shock

This is our pick for one of the best hot tub chemicals. Compatible with chlorine, bromine and ozone and ionization systems, it is perfect for hot tub use. It is ready for use and you can do it on your own. It features a pH buffer which keeps your spa water well balanced.


  • Can use it for hot tubs and spas
  • Easy to use and ideal for eczema
  • Will not affect the water pH level
  • Removes contaminants present in hot tubs


  • Purely for hot tub and spa use; cannot be used in swimming pools

SpaGuard will keep your water sparkling clean. Usage depends on your hot tub usage. It is super affordable too. Total worth for your money!

SpaChoice 472-3-5081 Chlorine Granules for Spas and Hot Tubs, 5 Pounds

This is one of the best chlorine sanitizers for hot tubs. With 56% available chlorine, it is super effective at killing bacteria and keeping those algae at bay. It dissolves quickly and thoroughly.  Distribute 3 tablespoons per 500 gallons of this product evenly in the deepest part of the pool with water circulating. Note that each tablespoon of SpaChoice will provide you with around 1.4 ppm available chlorine in 500 gallons water capacity.


  • Dissolves completely
  • Kills bacteria and algae thoroughly
  • Good quality and desired quality at an affordable price
  • Stabilized spa chlorine and UV resistant


  • Many users have faced packaging issues – they have had trouble with getting the bottle to open.
  • Comes in a large container

If you are looking for a chlorinated chemical to remove contaminants and bacteria at an affordable price and in good quantities, go for this product.

Leisure Time Spa 56 Chlorinating Granules

This chemical is designed to work with chlorine sanitizing systems in your hot tub and cleans your spa efficiently. Very easy to use, it dissolves quickly and completely. The special granular formula will help maintain your hot tub, clean, hygienic and transparent.

It effectively kills germs and bacteria, while also efficiently removes grease and other impurities. It will not upset the water balance, no no harmful side effects. It’s stabilized to protect against UV rays so it can be used as a crystal sanitizer too. Being buffered, it won’t change the water pH.

For shock, use 1oz.for every 500 gallons of water. For other usages, use ½ ounce per 500 gallons of water.


  • Works for spas, hot tubs and preheated pools
  • Maintains the natural pH of the water(no side effects for you because of imbalance)
  • Compatible with all purifying methods
  • Easy to apply and is long-lasting
  • Can also be used to give shock treatments to your spa and hot tubs


  • After a shock treatment, you may have to wait for a few days before you can use your hot tub
  • Just a tad expensive

This is without a doubt, one of the best hot tub chemicals to use. It works great on common contaminants and also gets rid of oils, cosmetics, ammonia etc to keep your spa water clear, clean and smelling great.

Leisure Time Spa Disinfectant Brom Tabs

There is no need for chlorine or bromine sanitizers if you use this. It works well with bromine sanitizing spa systems. These are slow dissolving tablets and low dust that will fit in most spa feeders and floaters. Formulated with 10 percent more active sanitizer, they are strong and effective in keeping your water crystal clear.


  • Comes with an advanced low dust formulation
  • Easy to use tablets and that ensure hassle-free maintenance of your hot tubs and spas
  • Concentrated bromine sanitizer


  • Some users had trouble with crumpled and broken arrival of these tablets
  • Dissolved a bit rapidly, according to some purchasers.
  • Few other sanitizers are available that are more effective in this range

For Bromine Sanitizing systems, you don’t have to look beyond brominating tablets from Leisure Time. It is a natural and eco-friendly mineral purification.

Oxy-Spa Oxidising Shock

This granular Monopersulfate Oxidising shock stands out from other brands in that it has the highest oxygen content. Apart from clearing water contaminants, it also gets rid of residual soaps, deodorants, cosmetics, natural oils and build-up in spa water. It will also rid the water off foul smells and clears cloudy waters.

The most appealing aspect is that you can start using the pool within minutes after treatment with this product.


  • More potent and high performing because of the highest concentration of active oxygen
  • Gets rid of a whole lot of contaminants and residual impurities along with microorganisms.
  • You can use your hot tub immediately after treatment


  • The pool water may turn grey after several uses.
  • The chemical comes in only 2/3rd of the packaging

Equipped with the highest Active Oxygen, it is one of the best chemicals for hot tubs. It comes in a handy 2-bottle package and is super easy to apply to keep your hot tub and spa clean like never before!

Leisure Time Bright and Clear

If you have trouble with the clarity and purity of your water and are looking for a chemical that can make cloudy and filmy hot tub water clean, fresh and neat in no time, go for this model from the reputed Leisure brand. Compatible with chlorine, bromine, ozone and biguanide sanitizers, it is specially designed for hot water use and delivers incredible results. This chemical works by suspending contaminants and clumping them together. They are then trapped easily in the filter and removed.


  • Compatible with many sanitizers
  • Prevents scale formation
  • Quick-acting
  • No waiting time after use


  • It might foam too much

If your hot tub gets muddy and murky quite often, this is one of the best options in the market. Use Bright and clear to make your spa water incredibly bright and clear.

SpaGuard Chlorinating Concentrate – 2 Pounds

This is a granular stabilizer that acts as both an oxidizer and stabilizer to maintain your hot tub well. It is one of the best hot tub chemicals for sensitive skin. It is a fast-acting formula, so you can use your hot tub almost instantly after treatment. You can use it directly without pre-dissolving.

It is affordable and compatible with chlorine and brominated spas and hot tubs using ozone and ionization systems.


  • Dissolves quickly. So you can use your hot tub immediately(yay I’m just as excited!)
  • Acts as an oxidizer and stabilizer
  • Requires no Pre-dissolving – easy to apply


  • We couldn’t find anything that could go wrong with this product actually. The size is small, maybe that’s a disadvantage for you? You decide!

If you are looking for an affordable yet high-performing product on a consistent basis, go for this chemical from SpaGuard. For those plagued by sensitive skin, definitely recommend it!

Clorox Pool & Spa 23006CLXCA

This chemical is dual-acting that can be used for pool sanitization and shock treatment. It dissolves super fast and removes harmful bacteria and all types of pool algae from your pool and hot tub spa. It analyzes your pool for free chlorine and bromine along with pH and alkalinity.


  • Removes all contaminants, be it organic waste or algaecide
  • Improves the performance of your filter
  • Suitable for salt pools and chlorine pools
  • Gives protection against the sunlight for greater durability
  • Reduces the bad odour of chlorine


  • It is not to be used for covered hot tubs
  • It may leave white flakes as residue

Giving you effective protection from algae and bacteria, it keeps your spa water bright blue, clean and neat. A pound of this chemical can effectively treat up to 53000 gallons of water! Avoid using it for covered hot tubs, or it can get messy!

Worthy Mention for kit

Hot Tub Things Chlorine Starter Kit – The only kit you will ever need to start a new hot tub. Inside the kit are chlorinating granules, pH and alkalinity down, pH and alkalinity up, spa clarifier, test strips and oxidizing spa shock.

Can you have a hot tub without chemicals?

You cannot maintain a hot tub without absolutely zero chemicals. While there are natural alternatives, completely avoiding chemicals will act as breeding grounds for bacteria, viruses and algae. These are unsafe to dip in and you run the risk of infection from contamination.

Chlorine is always better than bromine as we discussed in a section above. But if you over pour, it can still irritate your skin or eyes. If you are looking for options that are even more gentler on the skin, enzyme-based sanitizers like Zodiac Nature 2 Spa, Spa Guard Nature Spa Enzyme, Baqua Spa and Spa Marvel are all excellent, completely natural hot tub sanitizers.

Let us now take a look at some of the hot tub chemical alternatives.

  • UV(Ultra Violet) System – It keeps your spa sanitized through radiation as the water passes through the tube with UV bulbs. While a great alternative to chlorine, it does nothing to keep the water clear, so you will still need to shock your hot tub and even supplement it with a little bromine/chlorine.
  • Salt-based Systems – These systems are very popular. Saltwater is easier on the eyes than chlorinated water. Not only do they eliminate the need for chlorine or bromine, but they are also odour-free and gentle on the skin and eyes.
  • Biguanides – A good alternative to chemicals, polyhexamethylene biguanide(PHMP) comes with some benefits: it doesn’t break down like some chemicals, no unpleasant smell and gentler on the skin and eyes than chlorine. However, it doesn’t interact well with chlorine or bromine. To keep your tub sanitized, you still have to shock it without chlorine or bromine.
  • Ozonators – Hot tub ozonators inject ozone into the water to kill bacteria and sanitize it. With ozonators, the water stays cleaner for longer because it is much more powerful than chlorine or bromine. It may be expensive, and you still have to use some chemical sanitizers and also give shock treatment, but not often.
  • Ionizers – They work by releasing copper and zinc ions into the water. They effectively kill bacteria and contaminants but don’t prevent clouding. Also, you may need to supplement with small amounts of chemicals, either chlorine or bromine.

We just covered some of the best chemicals to use for your hot tub to keep it clean, usable and healthy. Particularly, if you have sensitive skin, some of the alternatives to chemicals will really come in handy. Don’t let sensitive skin come in the way of enjoying your hot tub! Happy dipping!

Recent Posts