Balancing and pH Alkalinity

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pH measures the level of acidity in your water. An improper pH reading can cause you to experience itchy skin, eye irritation, and if left uncorrected, it quickly deteriorates pillows, spa covers, and eventually your internal spa equipment. Therefore, pH is an essential element to keep properly maintained.

Alkalinity is a buffering agent, and its job is to help keep your pH stable. Low alkalinity can cause erratic changes in your pH, and high alkalinity can raise your pH level and makes it hard to correct.

There are several options for getting the pH and alkalinity in check. Most are pH up, pH down, alkalinity up, and alkalinity down, or you can find a product that raises both pH and alkalinity and lowers both pH and your alkalinity at the same time.

Using just two products instead of four makes caring for your spa a lot easier and less expensive.

The pH level in spa water should always be between 7.2 and 7.8, and the alkalinity level should be between 80 to 120 parts per million.


To raise your pH or alkalinity, first, turn off all the jets.
If your pH is reading between 6.8 and 7.2 in a spa up to 500 gallons, you should add just one ounce of pH alkalinity increaser. If your pH reads below 6.8, then add two ounces.

In large hot tubs or swim spas with up to or over 1,000 gallons, you should double these amounts.

For best results, premix the product in a small bucket of spa water and pour it back in as close to the center of the spa as possible.

Then turn on your filtration pump, wait 3 hours and retest the water. If it is still low, repeat this procedure.


To lower your pH, in a spa up to 500 gallons, first premix a ½ ounce of pH alkalinity decreaser in a small bucket of spa water. Then, turn on your primary pump at high speed and pour the premixed solution along the inside perimeter of your spa.
Wait 15 to 20 minutes and test again. If necessary, repeat this procedure, but never add more than 4 ounces in 24 hours.

To lower the alkalinity, first, make sure the pumps are off, and the water is calm. Then premix one ounce of pH alkalinity decreaser in a small bucket of spa water. Next, pour the solution back into the spa, as close to the center as possible, and wait one minute. Then, turn all pumps on high speed for 20 minutes and retest the water. Repeat this step if necessary.

Keep in mind. It is more important for the pH to be accurate than the alkalinity. So, if your reading shows the pH and alkalinity are low, follow the procedure for pH.