How much

How much sand for a 180 gallon?

Pre-calculated for the 180 gallon (72 × 24 × 25 in · raw volume ≈ 187 US gal · water volume ≈ 170 US gal).

By scenario

ScenarioAmount
1" shallow / aesthetic bed

85 lb

5 × 20-lb bag. No denitrification. Acceptable for SPS frag tanks.

2" standard sand bed (most reefs)

170 lb

9 × 20-lb bag. Best look-to-maintenance ratio for mixed reefs.

4" deep sand bed (DSB)

340 lb

17 × 20-lb bag. Provides anaerobic denitrification. Old-tank-syndrome risk after 5+ years.

Bare bottom

0 lb

Frag tanks, ULNS, maximum-flow setups. Best detritus visibility.

Brands hobbyists actually use

Aragonite bags. Special Grade is the modern reef default; Pink Fiji is finer.

Affiliate links. As an Amazon Associate, reefcalcs earns from qualifying purchases.

Last reviewed