Fish Tank Volume Formula
The fish tank volume formula depends on the tank shape. For a rectangular aquarium it is simply length times width times height. Cylinders, hexagons, corners and other shapes each use their own formula, listed below. Enter your measurements in the calculator for instant litres and gallons, or work it out by hand using the formulas here.
Volume formula for each tank shape
V = length Γ width Γ height V = lengthΒ³ V = (l Γ w Γ h) + Β½ rΒ² (Ξ± β sin Ξ±) Γ h V = ΒΌ Γ Ο Γ length Γ width Γ height V = Ο Γ (diameter / 2)Β² Γ height V = Ο Γ (diameter / 2)Β² Γ height / 2 V = Ο Γ radiusΒ² Γ height / 4 V = (3β3 / 2) Γ sideΒ² Γ height V = Β½ Γ length Γ width Γ height V = 2(1 + β2) Γ sideΒ² Γ height V = 1.720 Γ sideΒ² Γ height Worked example: a rectangular tank measuring 60 by 30 by 30 cm has a volume of 60 x 30 x 30 = 54,000 cubic centimetres. Divide by 1,000 to get 54 litres, or by 3,785 to get about 14 US gallons.
To convert the result, divide cubic centimetres by 1,000 for litres, cubic inches by 231 for US gallons, or by 277.4 for UK gallons. One litre equals 1,000 cubic centimetres, one US gallon is 3.785 litres and one UK gallon is 4.546 litres.