Water Chemistry /
How to Bring Up pH in a Pool Safely
If pool pH is low, test the water first, check total alkalinity, then use a pH increaser per the label. Keep circulation running and retest.
Archive date: this article was written for PoolSkimmer on Oct 23, 2026 and given the earlier archive date of May 31, 2026 so the blog reads as an organized archive. It was not published on that date.
The surest way to correct a low pool pH is to test and verify the reading before applying any chemical, and to do so in strict accordance with what the label says. It is also wise to look at total alkalinity in many cases since the two are interrelated. Make sure the pump is on for proper circulation and retest prior to any other adjustments.
Precautions before raising pH
One number does not tell the whole story of your water balance, so put aside a reliable test strip or an approved method and take stock of the situation. A low pH can be symptomatic of several things. You should be looking at:
- pH and total alkalinity
- sanitizer levels
- the state of the pump and filter
- overall water clarity
Should you find the water is green or cloudy, or that the circulation is weak, simply putting in more pH increaser will not fix it. In fact, poor circulation can obscure the real problem and make balancing more difficult.
The right product for the job
When pH is low, a pool pH increaser is the straightforward solution. Soda ash is typical, though some may turn to baking soda or sodium bicarbonate if they also want to put up the alkalinity. But do not assume a one size fits all approach.
Let the test results dictate the treatment:
- Low pH with low alkalinity? Alkalinity likely needs to be addressed first.
- Is the pH down but total alkalinity in range? An increaser is probably the way to go.
- In doubt? Put it off and ask a professional at the pool store.
Under no circumstances should you mix chemicals or try to make do with household items. Stick to the manufacturer’s directions.
Raising pH the right way
There is a method to it:
1. Run a test on the water. 2. Verify the low pH and take note of the alkalinity. 3. See that the filter and pump are in good working order. 4. Consult your manual and the product label. 5. Introduce only the designated pH product and let the system circulate it. 6. Give the water time to mix and then retest.
Unless the label indicates otherwise, do not put multiple chemicals in at once. Handle them in a well ventilated space with the appropriate PPE.
Why the numbers won’t hold
You may find the pH drifting back down after you have set it right. This is not random; it could be due to rain, fill water, a lot of swimmers, or water features that add aeration. Low total alkalinity is another culprit, as is a filtration issue. Think of alkalinity as a buffer for the pool – managing it properly will keep the pH from fluctuating as much.
Time to call in an expert?
If you are dealing with test results that don’t add up, or if the pH and alkalinity are proving unmanageable, it is best to get some qualified assistance. The same goes for equipment that is not functioning as it should, or if the water has become unsafe or irritating. And if there is even a hint of an electrical fault, stay out of the water and have a pro look at it.
As a matter of safety, never put your hands in operating suction equipment and shut off the pump before you clean the skimmer basket. Always follow the equipment manuals and chemical labels for safe operation.
Sources and further reading
- [Hayward: Weekly pool maintenance](https://www.hayward.com/maintenance/weekly-pool-maintenance)