78°F is the sweet spot for pool temperature.

Yes. For most residential pools, 78°F balances comfort with chemical efficiency. Colder than that and most swimmers aren’t happy; warmer and you’re breeding algae and burning through chlorine.

At 78°, your body can generate enough heat during moderate swimming to stay comfortable. It’s cool enough that bacteria and algae grow slowly, and chlorine stays effective without needing as much shock treatment. Push it to 82° or higher and you’re basically running a bathtub—algae love it, your sanitizer works harder, and you’ll spend more on chemicals.

If you have young kids or elderly swimmers, you might bump it to 80°—that’s still manageable. But every degree above 78° adds about 10-15% to your heating bill and makes chemical balance trickier to hold.

Think of 78° as the Goldilocks number for both your body and your wallet.