Inputs used
Assumptions for this answer.
- Pool volume
- 15,000 gal
- Turnover target
- 8 hours
- Filter max flow
- Not entered
Pool answer
What size pump for a 15,000 gallon pool?
For a 15,000 gallon pool, an 8-hour turnover needs about 31 GPM before checking pump curves, filter limits, and plumbing resistance.
Customize in the Pool Pump Size CalculatorAnswer table
Calculated result.
Required flow 31 GPM
Turnover time 8 hours
Status Planning flow
Formula
The math behind this answer.
Required GPM = pool gallons / turnover hours / 60
Substituted values
15,000 gal / 8 hours / 60 = 31.3 GPM
Source note
Pump answers use turnover flow math only: gallons divided by target hours and 60 minutes. Final equipment selection requires pump curves, filter maximum flow, plumbing resistance, and manufacturer instructions.
Scenario notes
Why this example may not match your pool exactly.
- At this size, turnover math is useful as a starting point before checking filter and plumbing limits.
- This example uses an 8-hour turnover target because it is easy to compare, not because every pool must turn over once every 8 hours.
- For a common backyard pool, the next constraint is usually filter flow rating, plumbing resistance, heater minimum flow, or pump-curve output.
Related calculators
Adjust the answer for your pool.
These answer pages use fixed assumptions. The calculators let you change gallons, readings, products, and targets.
Pool Pump Size Calculator Estimate required GPM from pool gallons and turnover time, then compare the flow to filter limits and pump curve planning. Pool Volume Calculator Estimate gallons for rectangular, round, or quick surface-area pool measurements before dosing chemicals. Pool Heating Cost Calculator Estimate the cost to heat a swimming pool from gallons, temperature rise, heater type, energy price, and efficiency or COP.
Answer FAQ
Common follow-up questions.
Use these answers to decide when the worked example is close enough and when to open the calculator.
How many GPM for a 15,000 gallon pool?
For an 8-hour turnover, about 31 GPM before checking filter limits and pump curves.
Is GPM the same as horsepower?
No. Horsepower alone does not tell you the flow at your plumbing resistance. Use pump curves and equipment ratings.
Can I use a longer turnover time?
A longer turnover time lowers the required GPM. Use the live pump size calculator to compare runtime targets.