How many gallons in a 21×41 ft oval pool?
A 21×41 ft oval above-ground pool holds about 20,200 gallons (76,600 liters) with 4 ft of water.
By water depth
| Water depth | US gallons | Liters |
|---|---|---|
| 3.5 ft (42 in) | 17,700 | 67,000 |
| 4 ft (48 in) | 20,200 | 76,600 |
| 4.5 ft (54 in) | 22,800 | 86,200 |
Formula: 3.14 × 20.5 × 10.5 × depth × 7.48. Measure the water, not the wall: water usually sits 4–6 inches below the top rail.
At 4 ft of water
Dose this pool: full chemical calculator · liquid chlorine · salt
Other oval pool sizes
12×24 ft oval · 15×30 ft oval · 16×32 ft oval · 18×33 ft oval
Questions pool owners ask
How many gallons are in a 21×41 ft oval pool?
About 20,200 gallons at 4 ft (48 in) of water. At 3.5 ft it holds about 17,700 gallons and at 4.5 ft about 22,800. Formula: 3.14 × 20.5 × 10.5 × depth × 7.48.
How much salt does a 21×41 ft oval pool need?
Starting from fresh water, about 540 lb of pool salt (14 × 40 lb bags) reaches 3,200 ppm at 4 ft of water. Add 80–90% first, then test after 24 hours.
How much liquid chlorine for a 21×41 ft oval pool?
Raising free chlorine by 1 ppm takes about 25.9 fl oz of 10% liquid chlorine, or 1.31 qt (42 fl oz) of 6% bleach.
How long does it take to fill?
With a garden hose at about 10 gallons per minute, roughly 34 hours. Two hoses halve that.