Hot Tub Knowledge

What Chemicals Do I Need for a Hot Tub

Once you have bought a hot tub, you have to learn a thing or two about hot tub chemistry. As a first time user of a hot tub, you might wonder: what chemicals do I need for a hot tub? We will try to answer this question in this post. We hope you will find the post helpful.

Hot tub chemistry is not rocket science. You just have to know what chemicals to use. The chemicals usually include sanitizers, pH levels, alkalinity, and shock treatments. The terms might sound frightening, but trust me, you do not need to be a chemist to understand them.

Total Alkalinity

First of all, the total alkalinity has to be measured and adjusted. You can properly adjust the pH levels only when the level of total alkalinity is ideal. 80-120 ppm is the ideal level of total alkalinity.

As a new owner of a hot tub, you may ask: what chemicals do I need for a hot tub? While there are several important chemicals, first of all, you have to make sure that the total alkalinity is adjusted. It will be hard to adjust the pH if the level of total alkalinity is improper. It can also lead to cloudy water, corroded equipment, and skin irritation. To do it properly, make sure you read the package instructions.


It is the relative basicity or acidity of the water. If the pH scale is lower than 7, the solution is acidic. And if the scale is higher than 7, the solution is basic. A slightly basic solution, which is 7.2 to 7.6, is ideal for the water of your hot tub.

If the water is too basic or too acidic, you have to correct the level by adding pH up or pH down. Before you test again, the water should be allowed to filter for about 30 minutes. If the pH levels are improper, you may experience skin or eye irritation. It can even damage your tub.

Depending on your needs, you will have to use a pH decreaser or pH increaser. Your goal is to bring the alkalinity level down to the suggested range. Remember, the pH levels in your hot tub water will not be stable; it will increase or decrease.

Water Sanitizer

To sanitize water, make sure you do not use chlorine and bromine solutions together. When you are using bromine to sanitize water, you just have to drop a tablet in the water. Chlorine is usually a granular powder that has to be added to the pool water. When you add the chemical, you must frequently test the water to make sure that the levels are appropriate. The readings should be consistently balanced.

You have to know a few things before you use chlorine or bromine in a spa. Experts usually recommend bromine because it is a better sanitizer in the long run. But bromine is more expensive. However, if you consider its power, the cost is worth it. This powerful sanitizer kills viruses and bacteria and does not cause skin irritation.


Cleaning Chemicals

You are probably still wondering: what chemicals do I need for a hot tub? Apart from other chemicals, you have to use some cleaning chemicals. In a sense, cleaning chemicals are the most important. The reason is simple. Cosmetics, soap residue, and body oils cause scum build-up. a water clarifier is used to prevent them.

Water clarifiers work by reducing odors and preventing plug up. These enzyme-based products are biodegradable. In order to stop stain and scale formation, you have to use a  product designed for this purpose. Before you use any product in your tub water, make sure you read the instructions.

Here’s how to clean a hot tub without draining it.

Hot Tub Shock

This is a procedure to deal with water issues quickly. It works by raising the sanitization levels. It is a part of hot tub maintenance, and you have to do it once a week. If you have to use your hot tub for a while, consider a hot tub shock treatment.

After heavy use, if organic compounds are left in your tub, shock treatment can remove the compounds. For example, hot tub shock can make cloudy water clear in a very short time. What chemicals do I need for a hot tub?—you might wonder. The list of chemicals is incomplete without bromine and chlorine.

Chlorine shock treatment can kill bacteria. The treatment makes it easy to filter spent particles. Bromides work more effectively after a shock treatment.

Spa Fragrances

It is not necessary to use spa fragrances, but they can certainly make your hot tub experience more enjoyable. There are some spa fragrances that are particularly designed for hot tubs. If you are not allergic to perfumes, you can seriously consider adding spa fragrances to your hot tub water.


There are some chemicals that do not fit into any category. Foam out or foam down, enzymes, algaecides, and leak seal are such chemicals. At some point, you are going to need these chemicals. They can resolve many different types of water-related issues. Luckily, specialty chemicals are needed only rarely.

Testing Spa Chemistry

The water in your hot tub can be tested in two ways. You can use either a test kit or a test strip. Using a multi-purpose test strip is a good idea because it can test all important stuff in a couple of minutes. Spa chemistry is pretty simple, so you can easily understand it.

Every week, you should test your spa water at least twice. Try your best to maintain this regularity. You can also consider keeping a test log note. Every hot tub’s chemicals have a distinct personality, and this logbook will help you understand it. You might take some time to grasp it.

Storing Hot Tub Chemicals

Make sure these chemicals are not within the reach of children. They should be stored in a dry and cool place. Do not open multiple containers at a time. To keep out moisture, make sure the lids are tight. Chemicals should be protected from mixing, spills, and contamination.

You can dramatically prolong the shelf life of chemicals by storing them in temperatures ranging from 50-75° F. In this range of temperature, gas can not form and granules can not harden. If the lids are tight, small children will not be able to open the lids. Tight lids will also prevent accidental contamination, mixing, and spills.

Make sure the chemicals do not come in contact with dirt, leaves, or any other substance. If you allow the chemicals to mix with other substances, an explosion or fire could result. If you have old spa chemicals, dispose of them or use them up. And if you are living in an area that is prone to earthquakes, keep your chemicals on the ground floor.

What Chemicals Do I Need for a Hot Tub – Final thoughts

If you have recently bought a hot tub, you may wonder: what chemicals do I need for a hot tub? To get the best out of your hot tub, taking care of it is of utmost importance. We have tried to discuss all the chemicals needed for a hot tub. If you wish to learn more, you can do some research online.