Question: how to calculate water volume of a tank?
Answer: Multiply the number of cubic feet by 7.47 gallons to determine the number of gallons each container can hold. In the rectangular container example above with a volume of 8 cubic feet, 8 x 7.47 = 59.76 gallons. The volume in gallons of the round container is 56.66 x 7.47 = 423.25 gallons.