What Causes High PH In Hot Tub
Because your hot tub's pH level is the what keeps the water fresh and healthy to soak in, it's a crucial element to keep in balance.
Luckily, if your hot tub's pH level is too high, there are simple steps you can take to lower it.
Come with us as we explore what causes high pH levels and the maintenance needed to keep it in check.
Why Is the pH In Your Hot Tub High?
One of the main reasons that the pH is too high in your hot tub is that the total alkalinity in your water is too high. pH and alkalinity are related in many ways.
You can think of the total alkalinity in your hot tub as a buffer for the pH, which helps keep it in a healthy range.
If your hot tub's total alkalinity is not within a healthy range, then it will not be able to keep your pH level in the healthy range.
Your hot tub generates many bubbles with the jet system and operates at high temperatures. When you have tons of heat and bubbles, the combination can create carbon dioxide, which is a gas we are all very familiar with.
When carbon dioxide builds up in your hot tub, the pH level rises. For this reason, hot tub owners will often add products to lower the pH in their hot tubs, which will also lower the

total alkalinity. If you use well water as your source of hot tub water, you will likely have a harder time lowering your pH and alkalinity.
More often than not, straight or softened water that comes from the well will have higher pH levels and alkalinity levels.
To learn more, head over to our how to raise & lower alkalinity in a hot tub article.
Should I Worry About Hot Tub Scale?
If the pH is too high in your hot tub water, then you might end up dealing with the formation of scale. Scale comes around when you have a mixture of high water temperatures and a high pH level. Scale, which comes in the form of a chalky, white deposit, can also form if you have low calcium in your hot tub.
Scale feels a lot like sand when you touch it on the surface of your acrylic hot tub. There are many hot tub owners that say they even see the little white flakes from this scale coming out of the jets in their hot tub.
Not only does scale feel weird on the skin, but it can also clog up your jets and stop the water from circulating at an optimal level. In the end, this can create errors with your water flow, blocking the heater from working optimally, as well as the insides of the plumbing system.
If left to its own devices, scale will continue to form, which can eventually bring your heater to complete failure.
Lower the pH Level In Your Spa

If you want to effectively lower the pH level in your hot tub water, you should consider adding something like a pH reducer, which is a pH negative product.
There are many pH reducer products out there, though one of the most popular products out there is sodium bisulfate.
Sodium bisulfate comes in a dry, solid crystal form. You can think of it as dry acid. Anything that is lower on the pH scale is an acid.
It is highly recommended that hot tub owners add these types of products into their hot tubs if the pH is between 7.2 and 7.8. You can also add sodium bicarbonate to do the same thing.
When you are using one of these products to lower the pH in your hot tub, it is very important to add the amount that is designated on the instructions every day until you get the pH level where it needs to be rather than dumping it all in at once. If you add your pH reduction product to your spa water too fast, the water inside of your hot tub will become far too acidic and you will have to use a pH increase to bring it back up.
If you add the recommended amount of your pH reduction product for a lower pH and it doesn't lower the pH in your water chemistry, you can always add a form of liquid acid. Liquid acid is great for lowering the pH in your hot tub and acts far more aggressively to get the job done. Again, we recommend using a traditional reducer first before attempting to use a harsher liquid acid.
There is a good chance that your hot tub pH is higher than the level you are seeing when you use your test strip. Continue adding a pH minus product to the water, giving it 30-minute intervals to dissolve before using a test strip to test it out until you get the low pH that you desire.
Bringing Your Total Alkalinity Back Up
When you lower your hot tub's pH level, you might end up with a total alkalinity level that is too low, as alkalinity and pH go hand-in-hand. The good thing is, keeping your alkalinity and pH level in balance is pretty easy.
If you test your water chemistry and notice that the total alkalinity (TA) is too low after you add a low pH product, you can use soda ash or baking soda to bring it back up.
Baking soda in hot tubs works really well to raise the total alkalinity and is the preferred method for many hot tub owners, as it is readily available in just about any home. The beauty of baking soda is that it raises the total alkalinity in your hot tub without affecting the hot tub pH level very much.
On the other hand, if you use soda ash, it may have a pretty dramatic impact on the hot tub's pH level, meaning you might have to use a low pH product to get it back down, leaving you in an endless cycle of raising and lowering your hot tub pH and alkalinity levels.
Is High pH In Your Hot Tub Bad?
If you use test strips on your hot tub water and you realize that your hot tub's pH is high, you have a problem that you need to address right away.
There are many negative consequences that can arise when your pH is high, including:

Final Thoughts
Keeping everything in the proper range and in balance in your hot tub isn't a hard thing to do. Get yourself a spa test kit and start testing out the water in your spa to keep it at a consistently normal level. In doing so, you'll be able to enjoy fresh water in your spa more often.
