calcs.homes
calcs.homes
Enter your pool volume and target turnover time to find the flow rate you need, and a recommended pump size to hit it.
Estimate only — actual required HP also depends on pipe size, filter type, and plumbing run length.
We divide pool volume by your target turnover time (converted to minutes) to get the flow rate needed in gallons per minute. That flow rate is then matched against a horsepower lookup table — roughly 30 GPM for 0.5 HP, 50 GPM for 1 HP, up to 110+ GPM for 3 HP — to recommend a pump size.
8 hours is the standard residential turnover target because it lets a typical pool's full volume pass through the filter once during a normal day without oversizing equipment. The horsepower table is only a starting estimate, since actual pump sizing also depends on head pressure from pipe diameter, fitting count, filter type, and plumbing run length — factors a pool professional accounts for when sizing precisely.
It's how long it takes your pump and filter to circulate a volume of water equal to your entire pool. 8 hours is the standard target for residential pools, letting the whole pool filter once during a typical day.
No — oversized pumps waste electricity and can even reduce filter efficiency by pushing water through too fast. Variable-speed pumps sized to your actual flow needs are usually the most efficient choice.