If you mean 18 feet in circumference (around the outside measurement) Circumference = pi x D , 18 = pi x D , Diameter = 5.730 feet
Area = pi x r squared, Area = pi x 2.865 squared , Area = 25.787 sq. feet
Volume - 25.787 x 4 = 103.148 cu. ft. x 7.48 = 771.5 gallons If you mean 18 feet across (diameter)
Area = pi x r squared, Area = pi x 9 squared , Area = 254.47 sq. feet
Volume - 254.47 x 4 = 1017.88 cu. ft. x 7.48 = 7614 gallons
1,770 gallons.
2,360 gallons.
9,440 gallons.
26,550 gallons.
About 19,355 gallons.
6,200 gallons.
3,398.4 gallons.
5,974 gallons.
1,770 gallons.
Three feet of water in a 12-foot round pool is about 2,550 gallons.
About 212 gallons.
About 5,310 gallons.
About 13,010 gallons.
2,360 gallons.
9,440 gallons.
26,550 gallons.
About 19,355 gallons.