Calculate the exact amount of aquarium substrate needed. Enter tank dimensions and desired depth to get volume in liters and weight in kg or lbs. Supports rectangular, cylindrical, and bow front tanks.
Substrate is more than decoration: it is the rooting medium, the biological filter surface that often outweighs the canister filter itself, and the single largest source of long-term displacement in your tank volume. This calculator turns tank footprint and target depth into the kilograms or pounds of aqua soil, sand, or gravel you need to purchase, plus the water volume that substrate will displace once flooded. Buying the right amount the first time avoids costly re-orders, prevents the dreaded shallow front slope, and lets you plan stand load with confidence.
We multiply the wetted footprint (length times width, or projected area for cylindrical and bowfront tanks) by the target depth to obtain a gross substrate volume. That volume is then multiplied by the bulk density of the chosen substrate type: roughly 0.7 kg/L for porous aqua soils such as ADA Amazonia, 1.5 kg/L for fine pool-filter sand, and 1.6 kg/L for typical river gravel. A slope adjustment factor is layered in for aquascapes where the back is deeper than the front, and water displacement is reported so you can correct your net water volume for dosing.
Enter your tank's length, width, and desired substrate depth to calculate the volume and weight of substrate needed. The calculator supports aqua soil, sand, and gravel with different density values.
Planted tanks need 6–8 cm of substrate for healthy root growth. Fish-only tanks only need 3–5 cm. Choose the right depth based on your tank's purpose.
Aqua soil is nutrient-rich but lighter. Sand is ideal for bottom-dwelling fish due to fine particles, while gravel is durable and easy to clean. Match your substrate to your tank's needs.
Substrate depth depends on plant type. Rooted plants need 2-3 inches for root development. Carpet plants need 1-2 inches. Hardscape-focused tanks need minimal substrate. Deeper substrate retains more nutrients.
Common types include aqua soil (nutrient-rich), sand (fine, good for plants), gravel (various sizes), and inert substrates. Choose based on plant type and aesthetic preference. Some substrates affect water chemistry.
This calculator estimates substrate volume based on tank dimensions and desired depth. Actual amount needed depends on substrate density and packing. Buy 10-15% extra for adjustments.
Nutrient-rich substrates like aqua soil contain nutrients for plants. Inert substrates need fertilizer supplements. Liquid fertilizers supplement micronutrients. Test water parameters to determine what's needed.
Vacuum substrate during water changes to remove detritus. Avoid disturbing plant roots. Stir substrate occasionally to prevent anaerobic pockets. Replace substrate partially every 1-2 years as nutrients deplete.