Understanding Hot Tub pH

Ensuring that your chemicals are balanced can become a real headache if you are suffering from unstable pH levels and out of whack total alkalinity (TA) levels in your spa. Chasing the chemical levels up and down the test strips can drive you mad if you can’t seem to get it in perfect balance. Before the unbalanced pH starts causing scale build up, unsightly water or more serious concerns, let's talk about what why pH is important and how to keep it in that sweet spot. Having the correct chemical solution in your water is very important so you can worry less about the water chemistry and spend more time enjoying your spa.

  

pH

When we are talking about water pH, we are looking for the water to be as close to neutral as possible. As you may recall from high school chemistry, solutions can either be acidic, basic or neutral. When measuring pH with your test strips you are looking for the pH to be between 7.4 and 7.6 on the pH scale, which is considered neutral. Having a lower number on the scale means your water is more acidic and a higher number means it's more basic.

  • When pH levels in your spa exceed 7.8, your hot tub water is deemed basic. This can make it harder for your sanitizer to work correctly which in turn can leave you exposed to bacteria that can cause Legionnaires disease and hot tub folliculitis. Basic water is also liable to produce cloudy water and scale build up on the surfaces of the spa.
  • Low pH with any reading under 7.0 is acidic. This can also make your sanitizer less effective, leaving you exposed to nasty germs once again. Acidic spa water can also be corrosive to internal parts like jets and pumps, drastically shortening their life.

Total Alkalinity

Total alkalinity also plays a large role in keeping your pH in a balanced range. The phrase total alkalinity refers to the ability of a solution to neutralize acids, this is also known as buffering them. Having the alkalinity balanced in your hot tub water works as a buffer and allows your pH levels to stay more stable. This way you won’t be constantly adjusting your pH up and down.

  

The first step in your water maintenance routine will always be measuring and adjusting the alkalinity in your water before any other chemical. The perfect range for Total Alkalinity is 80 parts per million(ppm) to 150 ppm with 120 ppm being ideal.

  

When fine-tuning your alkalinity, add a small amount of product at a time, allowing it to circulate through the spa for 12-24 hours before testing again. Once you have the total alkalinity in the correct range, you can begin adjusting the pH levels. Accomplishing the correct ratio of alkalinity can also bring the pH back into perfect range as well. So when it comes to fixing the pH levels in you spa, start by adjusting your alkalinity to the optimal levels. If, after you test the water again, the water is still acidic (low pH), you will need a  pH increaser to bring the water back to neutral. If the water is on the basic side (high pH) you will need a  pH decreaser to bring the water back into proper range.

  

Tips

If you find that you are having to chase the pH to get it balanced, it may be time to drain the tub and start fresh. It is recommended that with average spa use the water should be drained and refilled every 3- 4 months. The day before you drain, add some  line and plumbing cleaner and run your pump and jets to clean out any buildup that may be affecting your water chemistry. After draining,  clean the inside of the spa thoroughly.

  

Using a pre-filter when filling can help to alleviate some initial causes of water chemistry problems. By helping to remove problematic metals and other contaminants the pre-filter can help to make balancing the water chemistry easier.

  

Keeping your filters, plumbing, jets and water clean and clear can help to prevent a lot of water chemistry problems before they start. Having a water maintenance routine and regular water changes every quarter will help to make water chemistry easier and hopeful take the frustration out of getting your pH balanced.