Aquarium Substrate Calculator
Free aquarium substrate calculator: pounds, kg, liters, and bag counts from tank footprint and depth. A 20-long needs ~21 lb of gravel per inch.
Aquarium Substrate Calculator
Substrate Needed
42 lb
In Kilograms
18.9 kg
Volume
11.8 L (0.42 cu ft)
Bags to Buy
2 × 20 lb + 1 × 5 lb
ℹ️ Slope the substrate higher at the back (e.g. 2″ front, 3″ back) for depth perception in planted tanks. Rinse gravel and sand before use; never rinse aqua soil.