Maintaining clean water: Everything you need to know about hot tub water chemistry

August 24, 2023 / Elicia Allott

Hot tubs often require regular maintenance to keep the water clean and safe to use, and one of the most important aspects of hot tub maintenance is maintaining proper water chemistry. Hot tub chemicals can be confusing but with the proper guidance, knowing how to use the correct chemicals will become a breeze. In this blog post, we’ll go over the basics of hot tub water chemistry and teach you how to use hot tub chemicals in your spa.

The water PH level

The first thing you need to understand about hot tub water chemistry is pH levels. pH is a measure of the water’s acidity or alkalinity, and it’s important to maintain a proper pH balance in your hot tub to avoid skin irritation, corrosion, and other problems. A pH level of 7.2-7.8 is considered ideal for hot tubs. You can test your hot tub’s pH levels using test strips, which are available to purchase here.


Sanitisers such as chlorine or bromine are used to kill bacteria and viruses in the water. Maintaining a proper sanitiser level is key to preventing illness and keeping your hot tub water clean. Test your hot tub’s sanitiser levels regularly and add chemicals as needed to maintain the proper level. We have different hot tub chemicals available to buy on our website.


Shocking is the process of adding a large amount of sanitiser to the water to kill bacteria and oxidise organic matter. Shocking is especially important after heavy use or if the water has become cloudy or discoloured.

Regular maintenance

Finally, it’s important to practice regular maintenance to keep your hot tub water chemistry in check. This includes testing the water regularly, cleaning the filters, and draining and refilling the hot tub periodically. Regular maintenance will not only keep your hot tub water clean and clear but also prolong the life of your hot tub. We stock a chemical starter kit which includes all the chemicals you’ll need to keep your hot tub in tip top condition.

Maintaining proper hot tub water chemistry is essential for health, safety, and the longevity of your hot tub. Remember to test your water regularly, add chemicals as needed, and practice regular maintenance to keep your hot tub healthy.


Q: How often should I test the water in my hot tub

A: It is important to test your hot tub water at least once a week and maintain proper chlorine, alkalinity, calcium hardness and pH levels. Testing the water regularly helps prevent algae growth, cloudy water, unpleasant odours and skin irritations.

Q: What is the ideal pH level for hot tub water?

A: The ideal pH level for hot tub water is 7.2 to 7.8 on a scale of 0-14, with 7 being neutral. Keeping the pH in this range ensures that all elements necessary for proper spa operation such as chlorine and algaecides remain effective and provide optimal sanitisation results.