Gallons:
Determining Pool Size (Gallons of Water in Your Pool)•
Rectangular Pools:Length x width x average depth x 7.5•
Circular Pools:Diameter x diameter x average depth x 5.9•
Oval Pools:Length x width x average depth x 6.7•
Sloping Sides:Multiply total gallons by 0.85 = gallon capacity
Liters:
Determining Pool Size (liters of water in your pool)•Rectangular Pools:Length x width (meters) x average depth x 1000•
Circular Pools:Diameter x diameter x average depth x 785•
Oval Pools:Length x width (meters) x average depth x 893•
Sloping Sides:Multiply total liters by 0.85 = liter capacity.
Source: Pentair Pool and Spa