Vertical Storage Tank Free standing with a flat bottom for indoor or outdoor installations. Tanks are manufactured from medium - or high - density polyethylene with U.V. inhibitors. These tanks conform to the requirements of NSF/ANSI Standard 61. Tank walls are opaque for level viewing and equipped with gallon indicators. Specific gravity is listed to the left. Tanks can be customized with a well pipe, foot valve, and shut off valve for chemical feed. Select Your Tank Above: VT0135-28 135 gallon 2.0 specific gravity, 47 lbs., 28”D x 59”H VT0160-28 160 gallon 2.0 specific gravity, 56 lbs., 28”D x 68”H VT0225-31 225 gallon 2.0 specific gravity, 67 lbs., 31”D x 76”H VT0300-35 300 gallon 2.0 specific gravity, 88 lbs., 35”D x 81”H VT0425-42 425 gallon 2.0 specific gravity, 101 lbs., 42”D x 75”H VT0500-46 500 gallon 2.0 specific gravity, 120 lbs., 46”D x 77”H F.O.B Will Apply Contact us for additional sizes. Tanks available from 50 gallons up to 6,000