How to work out pool turnover
turnover hours = gallons ÷ (gpm × 60) · daily cost = hp × 0.746 ÷ 0.8 × hours × price per kWh
Turnover is the time the pump takes to move the whole pool's volume through the filter once. A 20,000-gallon pool at 40 gpm turns over in 8.3 hours; a 30,000-gallon pool at 60 gpm also takes 8.3 hours. Home pools are usually run long enough for one full turnover a day, more in hot weather, heavy use or after a storm. One turnover does not filter every drop, since filtered water mixes back in, which is why the clearest pools run a little longer.
| Pool | 30 gpm | 45 gpm | 60 gpm | 80 gpm |
|---|---|---|---|---|
| 10,000 gal | 5.6 h | 3.7 h | 2.8 h | 2.1 h |
| 15,000 gal | 8.3 h | 5.6 h | 4.2 h | 3.1 h |
| 20,000 gal | 11.1 h | 7.4 h | 5.6 h | 4.2 h |
| 25,000 gal | 13.9 h | 9.3 h | 6.9 h | 5.2 h |
| 30,000 gal | 16.7 h | 11.1 h | 8.3 h | 6.3 h |
| 40,000 gal | 22.2 h | 14.8 h | 11.1 h | 8.3 h |
What the run time costs
A motor's horsepower × 0.746 is its output in kW; at about 80 % motor efficiency a 1.5 hp pump draws 1.4 kW, so 8 hours a day is 11.2 kWh, 1.68 USD at 0.15 USD per kWh and about 50 USD a month. A variable-speed pump turns the same water over at a fraction of the power, because power falls with the cube of speed: running twice as long at half speed uses about a quarter of the energy. Choosing a pump? Use the pool pump size calculator; for the filter it must feed, the pool filter size calculator; for your gallons, the pool volume calculator.
Formulas: gallons ÷ (gpm × 60) for turnover; 1 hp = 0.746 kW, motor efficiency 0.8 assumed. The 0.15 USD per kWh default is an example input, not an average: enter the rate on your bill. Read October 23, 2026.
Frequently asked questions
How long should a 10,000 gallon pool pump run?
Long enough for one full turnover a day: 10,000 gallons ÷ (gpm × 60). At 30 gpm that is 5.6 hours, at 20 gpm 8.3 hours. Run longer in hot weather, after heavy use or a storm, and when the water is not clear.
How many hours per day do I need to run my pool pump?
Divide your gallons by the pump flow in gpm times 60 to get the hours for one turnover, and run at least that long each day. With a pump sized for an 8-hour turnover, that is about 8 hours. A variable-speed pump can run longer at low speed for less money.
How much does it cost to run a pool pump for 12 hours a day?
A 1.5 hp single-speed pump draws about 1.4 kW, so 12 hours is 16.8 kWh. At 0.15 USD per kWh that is 2.52 USD a day, about 76 USD a month; use the rate on your bill. A variable-speed pump on low uses a fraction of that.
How long does it take for a 30000 gallon pool to circulate?
At 60 gpm one full turnover takes 30,000 ÷ 3,600 = 8.3 hours; at 45 gpm, 11.1 hours. The flow is set by the pump and the resistance of pipes, filter and heater, so read it from the pump curve or a flow meter.
Is one turnover a day enough?
For most home pools, yes, if the chemistry is right. Because filtered water mixes back into the pool, one turnover filters about two thirds of the water; extra run time helps when the water is cloudy, after heavy use or when algae is starting.