Run it 8 hours a day in summer.

Around 8 hours. That’s enough to turn over your pool’s water once, keep it clear, and not waste electricity.

Longer won’t hurt, but it’s overkill. Most modern pumps are efficient enough that 6–10 hours does the job. If your water looks good after 6, bump it to 8 for safety. If it’s green, go longer — but that’s a chemistry problem, not a runtime problem.

Split the runtime: run half in the morning, half in the evening. That keeps circulation when the sun is cooking and when people are swimming.

Your electricity bill will thank you.