Hot Tub Chemicals 101

Hot Tub Chemical Kit SetThe best hot tub chemical kit will keep your spa's water clean and safe.

Caring for a hot tub does not have to turn into a full time job. It pays to spend 10-15 minutes reading up and learning about the must-know spa chemical basics.  Great for your health and the health of your spa equipment too.

Hot Tub Chemicals 101

In this primer, we try to cut through all the scientific mumbo-jumbo and give you the bottom line.

We won't be the Hot Tub Chemicals for Dummies, but more like the Cliff Notes version of hot tub water care and maintenance.

What about Cheap Hot Tub Chemicals?
Cheap Chemicals are not cheap in the end if they are diluted.There are cheap hot tub chemicals on the market, but looking closer at the label shows how diluted or watered down they might be.

For instance the Spa Choice Bromine Tablets offers a higher concentration of effective sanitizer than cheap bromine which may only be 56% or less actual bromine chemical.

So there is a difference between getting good spa chemicals at a discount online price and getting cheap chemicals where you just need to use more to get the same water balance.

What Hot Tub Chemicals Do I Need? Understanding Spa Water Care Basics

Whether you will start up a hot tub that is newly refilled or maintain existing water, these are the water care products you will need to keep the occupants and the spa safe.

Fast answer: Refilling a Hot Tub

1) Choose a sanitizer (bromine tablets or granular chlorine)

2) Adjust pH with either pH Up or pH Down (increaser/decreaser) - You will need 1 of each

3) Test strips or water test kit - to measure sanitizer level, pH and alkalinity

4) Shock treatment - to reactivate bromine or chlorine to sanitize the water better (about weekly)

Additional answer - Maintaining Hot Tub Chemicals:

There are other chemicals that can solve special situations as needed such as foam down, spa bright and clear, Sparkle or other clarifier, Alkalinity adjustment, water hardness adjustment...  

It is important to understand the main chemicals needed first and then the water should, in most cases, be ready to use with proper pH and sanitizer level.


Bromine Based Full-Size Chemical Set

Chlorine Based Chemical Set

Bromine or Chlorine - Sanitizer

You will need either bromine or chlorine as your main sanitizer to keep bacteria growth under control in hot water.  While many hot tub owners use chlorine (use granular di-chlor not tri-chlor tablets that you put in a pool!), others prefer to use bromine pucks or tablets in a feeder.  Both are effective, but don't mix them.  Use test strips to test for sanitizer level.

Bromine is more effective in hot water, so it lasts longer because it has a higher offgassing temperature than chlorine which gasses off at 97 degrees. The higher the water temperature, the faster chlorine decays.  Bromine does not turn into vapor until about 140 degrees, well over the hottest spa temperature of 106.

Did you know that the effectiveness of chlorine decreases when the spa cover is left open?  Sunlight decays chlorine quickly and organic debris can be blown into the spa, so keep the spa cover when not in use. Besides, keeping the spa covered also saves energy.

Proper Water Balance in a Hot Tub

Keep sanitizer in the desired range as shown on spa test strips or in the spa water test kit. Chlorine should be maintained between 2.0 and 3.0ppm. Bromine should be maintained between 3.0-5.0ppm. Adequate sanitizer level assures that bacteria and pathogenic micro-organisms are killed.

Adjust pH to be between 7.2-7.6. Check the level on your test strip or test kit and add pH plus (up) or pH minus (down) to bring the pH into the correct range.  If pH is too high, scaling and cloudy water can occur and if pH is too low corrosion can occur.

Test Strip readings

Avoid stain and scale by adding a product like First Step (Spa Breeze) whenever refilling the spa (usually every 3 months or so depending on use).

Shock Treatment vs. Super Chlorination?

It is better to shock the water (usually about weekly) with a non-chlorine shock treatment such as Refresh or Renew.  Super Chlorination can be used to rid the spa of waste buildup before draining it or when buying a used spa and turning it on for the first time. Although Super Chlorination (5x the normal chlorine dosage) can oxidize stubborn waste, regular shock treatments are better for most purposes to reactivate the sanitizer since non-chlorine shock does not add sanitizer to the water, so the sanitizer level stays in the acceptable range and the spa can continue to be enjoyed.

Shock the water. Adding a non-chlorine shock treatment such as Refresh assures that organic contaminants like perspiration, body oils, shampoos, cosmetics and other contaminants are eliminated. The shock treatment also removes the bromamines or chloramines which can accumulate in the water and cause skin irritation and odor. These compounds are created when the sanitizer (chlorine or bromine) combines with organic contaminants in the spa water.

Whether you have a Jacuzzi, Cal Spa, Master or QCA Spa, the water needs to be treated just the same.

See a complete collection of  hot tub chemicals by SwimNSpa to choose from.

Alternative Hot Tub Sanitizing and Chemicals

There are several products on the market to help reduce the sanitizer needed in the hot tub such as ozone generators, UV generators, Frog and other mineral sticks and various additives.  Although these items help reduce chemicals needed, the spa still requires some sanitizer - either bromine or chlorine. 

There are also enzymes, silver based products and other additives that are used with varying degree of success, but the documentation and studies to prove these completely replace chlorine or bromine is still forthcoming.

Allergic Reaction to Hot Tub Chemicals

Although most people do not have problems with well-maintained pools and spas, an individual's tolerance to particular chemicals must be noted and alternatives sought to accommodate the spa owner.

In non-maintained hot tubs where the water is out of balance, dermatitis and allergic reactions can occur to even those individuals who are not allergic to a particular chemical used in hot tubs.

That is because if bacteria are allow to multiply in hot water, it can present a health hazard to everyone. This is why it is important to maintain appropriate sanitizer level, check the pH regularly and shock (oxidize) the water weekly for best water quality.

Hot tub rashSevere hot tub rash spread by bacteria (Pseudomonas aeruginosa) in a hot tub is usually referred to as hot tub folliculitis. Avoid skin infections and little red bumps on the skin by maintaining your hot tub chemical balances and sanitizer level.

If you do get this type of infection, a topical antibiotic can treat it. Be sure you have adequate bromine or chlorine levels and shock the water regularly with Refresh non-chlorine shock treatment.

If you are allergic to chlorine which is found in drinking water, swimming pools and treated water and does a great job of removing bacteria and germs, then you may want to use a different sanitizer.

If you are allergic to bromine, you may want to try chlorine or an alternate sanitizer.

Note that properly treated pools and spas do not have a strong chemical odor. Having a pungent smell is an indication the water is out of balance, needs to have a shock treatment or in the case of a spa that has been in operation for a few months, it may be time for that water change.

Bromine in spaBromine lasts longer in hot water than chlorine and is considered to be a milder form of chlorine sanitizer. It does a wonderful job of killing bacteria in a hot tub. It also is said to have less odor in general than chlorine.

Hot tub users are split about 50/50 when it comes to the choice of using bromine or chlorine as the main sanitizer. As long as one of them is selected to keep bacteria under control, you can enjoy your hot tub in comfort.

Reduce (but not eliminate) the amount of chlorine/bromine used in the water further by having an installed ozonator, using mineral sticks or other sanitizer reducing products found at Hot Tub Outpost.

Popular Hot Tub Chemical Brands

Brand name spa chemicals include Spa Breeze, Leisure Time, Spa Choice and Frog.

Get great prices and selection on:

Where to Buy Hot Tub Chemicals

Save tax and buy hot tub chemicals online right here at Hot Tub Outpost. If your order is over the minimum ($95) we'll even ship free - otherwise there is a low shipping charge which still beats driving around town searching for chemicals. Fast shipping as orders are usually filled within 1 business day with high stock levels maintained.

See our hot tub chemicals.