Garden & Water Utilities
Pool pump turnover.
How long does your pump take to push one full pool volume through the filter, how many hours must it run for your target, and is the flow enough? Enter volume and flow. Runs in your browser.
Pool and pump
Turnover results
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Worked example
A 15,000 gallon pool with a pump moving 50 gallons per minute: 15,000 / (50 × 60) = 5 hours per turnover. Two turnovers a day need 10 hours of run time. If the pump only runs 8 hours it manages 1.6 turnovers; to reach 2 in 8 hours it would need 2 × 15,000 / (8 × 60) = 62.5 gpm, 12.5 gpm more than it delivers.
How it works
Hours per turnover = volume (gal) / (flow (gpm) × 60). Run hours needed = hours per turnover × target turnovers. Turnovers in a run = run hours / hours per turnover. Flow needed = target × volume / (run hours × 60). Litres and litres per minute are converted to US gallons and gpm first.
What this is not. A turnover does not mean every drop of water is filtered exactly once, since water mixes. Real flow is lower than a pump’s rated flow once it pushes through the filter, heater and plumbing, so measure it if you can. Longer runs at lower speed with a variable-speed pump can use much less electricity for the same turnover. Heavy use, hot weather and debris may need more filtering, and public pools are regulated by local health codes.
Sources and basis (checked 2026-10-06): turnover is volume divided by flow, the standard definition used by pool equipment guides. Running a residential pool for one turnover every 8 to 12 hours (2 to 3 per day) is a common rule of thumb, not a published standard; check local codes and your pump manufacturer for requirements.
FAQ
How many hours should I run my pool pump?
Enough to turn the full volume over once every 8 to 12 hours is a common residential target, which means 2 to 3 turnovers a day. Divide your pool volume by flow to see how long one turnover takes, then multiply by your target.
What is a pool turnover rate?
The time for the pump and filter to circulate a volume of water equal to the pool. A 15,000 gallon pool at 50 gpm turns over in 5 hours.
How do I find my pump flow rate?
Use a flow meter if you have one, or read the pump curve at your measured head pressure. The rated maximum is higher than what you actually get with a filter and heater in line.
Can I run the pump less to save electricity?
Sometimes. Variable-speed pumps run slower for longer, using far less power per turnover. Keep enough circulation to keep sanitizer even and water clear.