All depends on how deep the water is.
You can wet the bottom with less than 1 gallon, but it'll take more than 1 gallon to fill it 10 ft deep.
If the circumference of the pool (the distance across it through the center) is 5 ft,
then every inch of depth takes about 12.24 gallons.
How many gallons will fit into a 24 foot diameter x 4 foot high round swimming pool
5284.62 gallons
18,000
5300 Gal
It is 30.6 cubic feet = 190.3 Imperial gallons.
13,346 gallons per vertical foot.
There is NO way to calculate this without knowing how deep the pool is filled!
10,408 gallons.
28 is the diameter of the pool and 4 is the height (depth). 1 cubic foot is approx. 7.48 gallons. A round swimming pool is a cylinder. So: pi x (28/2)2 x 4 = 2463 cubic feet, multiply by 7.48 = 18423.24 gallons
7,646.4 gallons are needed.
About 18,402 gallons.
About 24 gallons.