Pool Turnover Rate Calculator
Step 1: Determine Pool Volume
If you already know your pool volume in gallons, skip to Step 2.
Rectangular
Round / Circular
Kidney / Oval (Approx)
Step 2: Calculate Turnover Rate
Enter manually or use calculator above.
Check your pump's flow meter or manual. GPM = Gallons Per Minute.
Calculation Results
Turnover Time:
— hours
Cycles Per 24 Hours:
—
Status (Residential):
—
Optimization Recommendations:
Required GPM for 8-Hour Turnover:
— GPM
Required GPM for 6-Hour Turnover:
— GPM
Understanding Pool Turnover Rate
The turnover rate is one of the most critical metrics for maintaining a safe and clean swimming pool. It refers to the amount of time it takes for the circulation system to move the entire volume of water in the pool through the filtration equipment exactly once.
Why is Turnover Rate Important?
Without proper turnover, chemicals cannot mix effectively, and debris is not removed efficiently. A stagnant pool is a breeding ground for algae and bacteria. Health departments strictly regulate turnover rates for commercial pools to prevent waterborne illnesses.
- Sanitation: Ensures chlorine/sanitizer is distributed to all corners of the pool.
- Filtration: Ensures particulate matter is captured by the filter.
- Clarity: Prevents cloudy water caused by poor circulation.
The Formula
To calculate your turnover rate manually, you need two numbers: your pool's total volume (in gallons) and your pump's flow rate (in Gallons Per Minute, or GPM).
Turnover Rate (Hours) = Pool Volume / (Flow Rate GPM × 60)
The "60" converts the flow rate from minutes to hours.
What is the Ideal Turnover Rate?
Standards vary based on location and pool type, but general guidelines are:
- Residential Pools: Ideally between 8 to 12 hours. At minimum, the water should turn over at least once every 12 hours, though 8 hours is preferred during peak summer usage.
- Commercial Pools: Strict regulations usually require a turnover rate of 6 hours or less.
- Spas/Hot Tubs: Due to the high temperature and small volume, these require very fast turnover, typically 30 minutes.
How to Adjust Your Turnover Rate
If your calculation shows that your turnover time is too slow (e.g., it takes 16 hours to cycle the water), consider the following:
- Clean the Filter: A dirty filter increases resistance and lowers GPM.
- Check Pump Speed: If you have a variable speed pump, increase the RPMs.
- Clear Baskets: Ensure skimmer and pump baskets are free of debris.
- Check for Leaks: Air leaks in the suction side can drastically reduce flow efficiency.