7.4–7.6 is the sweet spot for pool pH.

Aim for 7.4 to 7.6. That’s the range where chlorine works best and the water feels comfortable on your skin and eyes.

Below 7.2 gets acidic – it’ll corrode your metal ladders, damage the liner, and sting like hell. Above 7.8 gets too basic – chlorine becomes way less effective (even if your test shows “free chlorine” is fine) and you’ll fight cloudy water and scale deposits.

To adjust: use pH increaser (sodium carbonate, often sold as “soda ash”) to raise it, or pH decreaser (muriatic acid or sodium bisulfate) to lower it. Add small amounts, wait an hour, retest. Don’t dump a full jug in at once – you’ll overshoot and play ping-pong all season.

Test your pH at least twice a week during hot weather. It drifts.

Testing weekly is cheaper than fixing a corroded pump.