Aquarium Substrate Calculator
Enter your tank's footprint and the substrate depth to get the volume, weight and number of bags of gravel or sand.
Substrate needed
32 kg
≈ 20 L of substrate
≈ 4 bag(s)
Assumes a typical gravel/sand bulk density of 1.6 kg/L. Fine sand and specialist aqua-soils differ — check your product's stated density. Reference information only.
How we calculate
We multiply length × width × depth to get the substrate volume, then multiply by a bulk density of 1.6 kg/L for the weight.
Use the tank's internal footprint, not its outer glass dimensions. A depth of 3–8 cm suits most planted and unplanted setups.
Bags are your entered bag size rounded up. Results are shown in kilograms and liters.
Frequently asked questions
- How deep should the substrate be?
- 3–5 cm is typical for unplanted tanks; rooted plants often want 5–8 cm. Deeper beds trap more debris and need more careful maintenance.
- How much does aquarium gravel weigh?
- Most gravel and sand sit around 1.6 kg per liter, so a 20-liter bed weighs roughly 32 kg. Lightweight aqua-soils weigh less — use your product's figure if it differs.
- Sand or gravel — does the calculation change?
- The volume is identical; only the density differs. This tool uses 1.6 kg/L; if your bag lists another density, scale the weight accordingly.
- Can I share my settings?
- Yes — press Share to copy a link that reopens the calculator with the same dimensions.