About the Aquarium Gravel Calculator
Substrate needed for a tank at your chosen depth, in kilograms and litres.
Also known as: substrate calculator aquarium, how much gravel for fish tank, sand for aquarium, aquasoil calculator.
How to use this calculator
- Enter tank length, tank width, substrate depth, substrate and the other fields.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
litres = length × width × depth ÷ 1000, then × density
Worked example
Using the values pre-filled in the calculator above:
- Tank length = 120 cm
- Tank width = 40 cm
- Substrate depth = 6 cm
- Substrate: Gravel (1.6 kg/L)
- Price per kg = 2.5
the calculator returns:
- Substrate needed: 46.08 kg
- In litres: 28.8
- Depth: 6 cm
- Coverage area: 0.48 m²