How much
How much rock for a 20 gallon high?
Pre-calculated for the 20 gallon high (24 × 12 × 16 in · water volume ≈ 16 US gal).
By scenario
| Scenario | Amount |
|---|---|
| Minimal aquascape (0.5 lb/gal) | 8 lb Modern open-aquascape look. Pillars, arches, lots of swimming space. Adequate filtration when paired with sump + skimmer. |
| Standard reef (1.0 lb/gal) | 16 lb Classic reefkeeping rule of thumb. Plenty of biofiltration, ample coral mounting surface. |
| Heavy rockscape (1.5 lb/gal) | 25 lb Old-school 'wall of rock' approach. More biofiltration than needed in a modern setup, but works. |
| Dry rock (TBS, Marco, BRS Reef Saver) | Same lb, different curing time Dry rock needs 4–12 weeks of cycling to colonize bacteria. Live rock from a reputable source ships with pods, sponges, and ammonia-oxidizing bacteria already on it. |
Brands hobbyists actually use
Dry rock cycles 4–12 weeks. Pre-seeded synthetic skips the wait.
Marco Rocks dry reef rock
Cured dry rock. Cycle 4–12 weeks. No pests.
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CaribSea LifeRock
Pre-seeded synthetic rock. No cycling wait, no pests.
View on Amazon →
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