How To Lower pH In A Hot Tub? Here Are The 2 Ways To Do It

In this article, we provide you with some of the best ways to reduce ph in your hot tub and help you to enjoy a healthier and more relaxing time in your spa.

If you want to lower your ph levels in your hot tub, you'll need to do it the right way. There are two ways to reduce your pH levels and make your hot tub more enjoyable. We'll cover these two methods in this article and give you some tips and tricks to make them easier to implement.

Why You Need to Lower pH If It's Too High

Your hot tub's pH shouldn't be higher than 7.6 but not lower than 7.4. Both extremes can mess with your hot tub's water chemistry, causing a lot of problems like skin irritation and corrosion of hot tub parts (highly acidic) or bacterial growth due to sanitizers not being able to do their job (highly alkaline).

how to lower ph in a hot tub featured image

The first thing you need to do is check your hot tub's total alkalinity (TA). If it's too high, your pH is likely very high as well. This usually happens after shocking your hot tub because it breaks down chloramines, turning them into chlorine. You can also check the pH using test strips just to be sure.

Lower pH Using Muriatic Acid

Probably the most common chemical used in every household, muriatic acid is an inexpensive way to lower your hot tub's pH. But we also know how extremely corrosive this chemical is, so we need to handle it with a lot of care. Muriatic acid is known to cause skin burns, eye damage, and nose and lung irritation.

lower pH using muriatic acid

Here's how you can safely use muriatic acid to lower the pH in your hot tub:

  1. Check your hot tub's pH level using test strips or test kits. You can get them from your local hardware store hot tub supplier.
  2. Wear protection like gloves, safety goggles, and a face mask before handling this chemical. This step is extremely important to avoid chemical burns just in case you splash it and to avoid inhaling the fumes.
  3. Dilute 1 part of muriatic acid into ten parts of water in a large bucket and stir it using a wooden stir stick. Refer to the package instructions as to how much you're going to need based on how many gallons your hot tub can hold and the current pH level.
  4. Pour the solution into the tub and turn on the jets for a few hours.
  5. Check the pH level using test strips and repeat the process if needed.

Lower pH Using Sodium Bisulfate (Dry Acid)

If you're not comfortable using muriatic acid in your hot tub, sodium bisulfate is just as good for lowering pH in a hot tub. It's milder and safer, although more expensive than muriatic acid. Still, it's an acid, so care should be given when using this chemical.

lower pH using sodium bisulfate dry acid

Here are the steps on using sodium bisulfate to lower pH in your hot tub:

  1. Check your hot tub's pH using test strips. Your aim is to get 7.4 to 7.6. See package instructions for the right dose based on your hot tub's pH level and capacity.
  2. Wear protective gear for your hands, skin, and eyes.
  3. Dissolve a proper amount of sodium bisulfate in a bucket of water, constantly stirring with a wooden stick. Make sure it's completely dissolved.
  4. Pour the solution into the hot tub and turn on the jets. Let it circulate for 3 to 5 hours.
  5. Check the pH level using test strips. Repeat the process until the pH level is low enough (7.4 to 7.6)


You can find other solutions over the internet on how to lower pH in your hot tub, but so far, these two prove to be the fastest and most effective. Always use protective gear when handling these chemicals. Read and follow the instructions carefully, and don't hesitate to ask your hot tub supplier if you have questions.