Volume of a Hexagon tank

[intarsiabox]

The area of a hexagon = length of one side (14") squared x 2.6

Volume is area x height.

Capacity in gallons = volume / 231

Therefore 14x14x2.6x28 = 14,268.8 cubic inches / 231 = 61.77 gallons

This is probably based on outside dimensions so actual volume would be a few gallons less.