Aquarium Calculator
Fish tank volume and true water volume, weight, substrate, heater and filter size.
About this tool
Choose a rectangular, bow-front or cylinder tank and enter its size in centimetres or inches, the depth of substrate and how far below the rim you fill. The calculator shows the tank's volume, the water actually in it, the filled weight, the substrate needed, and rule-of-thumb heater and filter sizes.
How to work out aquarium volume
Tank volume is length ร width ร height, and 1,000 cmยณ is one litre. A 60 ร 30 ร 36 cm tank holds 64.8 litres, about 17 US gallons. The water actually in it is less, because substrate fills the bottom and the water stops below the rim. With 5 cm of gravel and a 2 cm gap, this tank holds about 52 litres of water, the figure to use for dosing medicines, conditioners and fertilisers. Water weighs 1 kg per litre and wet gravel about 1.6 kg per litre, so this setup weighs about 67 kg before the glass, rocks and stand. Common rules of thumb for a tropical tank in a heated room are a heater of 1โ1.5 W per litre and a filter that moves 4โ6 times the tank's volume an hour. Bow fronts add roughly two-thirds of length ร bow depth to the footprint. Honest limits: bow-front volume is an approximation, and how many fish a tank can hold depends on each species' adult size, behaviour and needs, not just litres. Research each fish before you buy. The pool volume calculator handles ponds and pools, the volume calculator covers other shapes and the unit converter switches units.
Frequently asked questions
How many litres is my fish tank?
Length ร width ร height in centimetres รท 1,000. A 60 ร 30 ร 36 cm tank is 64.8 litres.
How much does a full aquarium weigh?
About 1 kg per litre of water plus about 1.6 kg per litre of gravel. A 60 ร 30 ร 36 cm tank with 52 litres of water and 5 cm of gravel weighs about 67 kg before the glass, rocks and stand.
What size heater does my aquarium need?
About 1โ1.5 W per litre for a tropical tank in a heated room, more in a cold room.
Is my data saved?
No. The calculation runs in your browser and nothing is stored or sent.