purpose
Aquarium Volume Calculator
Calculate the water volume and capacity of any aquarium or fish tank with our specialized aquarium volume calculator.
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Try an Example
Pick a scenario to see how the calculator works, then adjust the values
Standard 55-Gallon Rectangular Tank
A popular community tank (121 × 30 × 51 cm internal dimensions).
Key values: 121 cm · 30 cm · 51 cm · ≈ 185 L
Nano Cube Desktop Tank
A 30 cm × 30 cm × 30 cm nano cube for a shrimp colony.
Key values: 30 cm cube · V = 27 L
The Aquarium Volume Calculator helps aquarium enthusiasts determine the exact water volume of fish tanks. Knowing your tank's true capacity is essential for proper fish stocking, water changes, and medication dosing.
Pro Tip
For bow-front or hexagonal aquariums, calculate using the rectangular portion and add the additional volume separately, or use the standard dimensions as an approximation.
Stocking Guidelines
A general rule for freshwater aquariums is one inch of adult fish per gallon of water. For saltwater tanks, use one inch per two gallons.
Volume Displacement
Remember that decorations, substrate, equipment, and rock work reduce the actual water volume – typically by 10-15% depending on the setup.
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