Maintaining the right balance of chemicals in your hot tub ensures your hot tub water is always clear clean, and safe for you and your family. If the water becomes too alkaline or too acidic, it can appear cloudy or smell bad, cause chemical irritation for bathers, corrode your hot tub equipment, and allow potentially harmful bacterial to grow. It’s therefore important to test your hot tub water once or twice a week, and then adjust the chemical levels as needed based on the results. There are two main ways to test your hot tub water at home:

Test Kit

Test kits measure your hot tub water chemistry using reagents, which are substances that bring about chemical reactions. To perform the test, you simply take a sample of your hot tub water using the kit’s plastic tester, add the reagent to your sample, wait 15 seconds, and then compare the sample’s colour changes to the chart on the test kit container. Test kits typically check chlorine and pH levels, with phenol red (red) reagent used to check pH and OTO (yellow) used to check chorine. It’s important to follow the directions carefully when using a test kit because adding an extra drop of reagent to your sample water by mistake can cause an inaccurate reading. Test kits are exceptionally accurate when used correctly, and many people find the colour changes are more distinct than that of test strips.

Some test kits use phenol red and OTO tablets rather than liquids. Therefore, instead of adding liquids to your water sample, you add a tablet to each chamber in the plastic tester, place the lid on, and then shake the tester until the tablets dissolve. You then compare the sample’s colour changes to the test kit colour chart, just as you would when using liquid reagents.

Test Strips

Test strips are arguably the easiest and most common method of testing the water in your hot tub. You simply take a sample of your hot tub water in a clean glass, dip the strip into the water to moisten the test pads, and then wait for about 15 seconds. Like with test kits, you compare the colour of the test pads to the colour chart on the test bottle to determine if your water chemistry matches the ideal ranges. Most strips test for chlorine/bromine levels, pH and alkalinity.

Test strips are at least as accurate as test kits, and are often considered to be more accurate because they are so simple to use. It’s easy to make mistakes measuring samples and counting drops with test kits, but the simplicity of test strips reduces these inaccuracies caused by human error.

In addition to these two at-home testing techniques, it’s not a bad idea to have your hot tub water checked by a qualified pool or spa professional once a month. Professional water testing provides a more in-depth analysis, typically screening for properties that test strips and test kits are not able to measure.

Stop by one of our locations across Ontario and our pool experts can professionally test your hot tub water, or guide you through the different at-home testing methods.