Aquariums · Calculator

Substrate volume

Substrate volume for a tank footprint plus depth. Estimates bag counts for common aquasoil, sand, and gravel products.

Substrate volume and bag count Dimensions in cm
Depth at the viewing pane. Carpeting plants want about 58 cm.
Depth at the back glass. Stem and root plants want about 810 cm.
Total volume -- L
Approximate weight (dry) -- midpoint estimate; sand is heavier, aquasoil lighter
Bag counts
ADA Amazonia (9 L)--
Fluval Stratum (8.8 lb, about 4 L)--
Eco-Complete (20 lb, about 7 L)--
CaribSea Peace River (20 lb, about 7 L)--
Pool filter sand (50 lb, about 15 L)--
Bag volumes are approximate, treat as starting points. Buy one extra bag for any tank over 110 L or any aquascape with hardscape, since substrate is annoying to short on and easy to store extra of.

How this works

Volume math is simple: length × width × average depth. The "front" and "back" depth inputs let you slope your substrate, which most aquascapers do (shallower at the front for viewing, deeper at the back for stem plants and root depth). The calculator averages the two.

Bag counts

The product list is approximate. Bag volumes vary by manufacturer and by how compacted the substrate is on arrival, so treat these as starting points. Buy one extra bag if your tank is large or the build is unforgiving (planted aquascape with hardscape, fully covered substrate). Substrate is annoying to short on, easy to store extra of.

Bag volumes used:

  • ADA Amazonia: 9 L per bag (the standard import size)
  • Fluval Stratum: about 4 L per 8.8 lb (4 kg) bag
  • Eco-Complete: about 7 L per 20 lb (9 kg) bag
  • CaribSea Peace River: about 7 L per 20 lb (9 kg) bag
  • Pool filter sand: about 15 L per 50 lb (22.7 kg) bag

The bags sold by weight are converted at dry bulk density: sand and gravel run about 1.5 kg per liter dry, so 50 lb of sand is about 15 L. If your bag lists a volume, trust the bag over this table.

Depth recommendations

For carpeting plants like dwarf hairgrass or monte carlo, 5 to 8 cm (2 to 3 in) at the front. For stem plants and crypts, 8 to 10 cm (3 to 4 in) at the back. For root-heavy plants like swords, 10 cm (4 in) plus. Deeper substrate is harder to keep clean and traps gas pockets if it sits undisturbed, so don't go deeper than your plants need.

Related tools

  • Tank weight - Add substrate weight to total floor load.
  • Stocking - Build a roster for this tank.

Further reading