What Is Hot Tub pH?

Hot tub pH is the measurement of the relative acidity or basicity of your spa’s water.  The pH scale runs from the most acidic measurement of 1 to the most basic measurement of 14.  A measurement of 7 is considered neutral.  Ideally, you want to keep the pH level of your hot tub water in the range of 7.2 to 7.8, or somewhat basic.  Having your hot tub pH levels outside of this optimal range can cause problems for both the bathers and the hot tub equipment, so it’s quite important to measure the pH level every week or more if you use your hot tub frequently.

Testing and adjusting pH levels is not very complicated and you can take care of it yourself. In the article below, you will learn exactly what you need to know about keeping your hot tub’s pH level properly balanced.

pH Testing

The two most common types of pH testing kits are testing strips and titration tests.  Testing the water pH with strips is easier to do, but slightly less accurate than titration tests.  To measure pH with a testing strip, you simply dip the paper strip into a sample of the water and compare the resulting color with a corresponding chart.  The color of the testing strip will tell you the approximate pH of the water.  With titration testing, you add a chemical reagent into the water sample and the slowly add drops of an indicator solution until the sample changes color.  The amount of indicator added will give you your pH measurement.  Although both these tests are quite simple to do at home, if you feel uncomfortable performing them, most hot tub dealers can test your water for you.

Low pH

If your water has a pH measurement of lower than 7, it’s considered acidic.  Acidic water can cause metal components of the hot tub to corrode as well as causing skin and eye irritation.  It may be possible to remedy this by simply adding fresh water.  Most tap water is slightly basic, so adding it to an acidic hot tub will raise the pH levels.  If adding fresh water isn’t enough to get the pH measurement to the right level, you’ll need to add a pH increaser until you get it in the range of 7.2 to 7.8.

High pH

If your hot tub water is too basic (ie. It has a pH measurement of more than 7.8) it can cause what’s known as water scaling.  Water scaling is a phenomenon where salts such as magnesium or calcium precipitate out of the water and accumulate on components of the hot tub such as its jets, filters, and pipes.  Excess scaling can cause these components to fail, so it’s important to remedy the situation.  Lowering high pH measurements is accomplished by adding acid to the water.  There are two main types of acid used to do this: dry and muriatic.  Although they both accomplish the same thing, their application is different, so it’s important to follow the directions depending on which type of acid you’re using.

Now that you know what hot tub pH is, learn more about hot tub maintenance by downloading a hot tub buyer’s guide.