SkimmerSkimmer
Chemistry

Ideal pool ph range

Ideal range
7.4-7.6
Acceptable range
7.2-7.8

What is pH?

pH measures how acidic or basic your pool water is on a 0-14 scale, with 7 as neutral. Pool water is kept slightly above neutral to stay close to the pH of the human eye and skin.

Why it matters

pH outside the acceptable range irritates skin and eyes, and it changes how well other chemicals work: low pH corrodes metal equipment and pool surfaces, while high pH clouds the water and makes chlorine far less effective at sanitizing.

How to raise pH

Add a pH increaser (typically sodium carbonate, sold as soda ash) in small doses, retesting between additions since it acts quickly.

How to lower pH

Add a pH decreaser (sodium bisulfate or muriatic acid) in small doses, and aerate the water afterward if total alkalinity is also on the high side.

How often to test

At least weekly; most pool professionals recommend testing more often during heavy swimming use or after rain.

Free tool
Skimmer can calculate this for you.

Get the exact dose to bring pH into range for your pool's volume — free, instant, no sign-up.

Open pH Calculator

Track this with Skimmer — log water tests and keep every reading in one place.

See pricing →
Frequently asked

Questions about pH

What's the ideal range for pH?
The ideal range for pH is 7.4-7.6, with 7.2-7.8 as the wider acceptable range before it's worth correcting.
How do I raise pH?
Add a pH increaser (typically sodium carbonate, sold as soda ash) in small doses, retesting between additions since it acts quickly.
How do I lower pH?
Add a pH decreaser (sodium bisulfate or muriatic acid) in small doses, and aerate the water afterward if total alkalinity is also on the high side.
How often should I test pH?
At least weekly; most pool professionals recommend testing more often during heavy swimming use or after rain.