Live Rock

Definition

Live rock is calcium-carbonate rock (typically aragonite-based) populated with beneficial bacteria, microfauna, and sometimes coralline algae. Forms the primary biological filter + biodiversity foundation of a marine tank.

Practical use in aquariums

Sources: aquacultured (best - sustainable, no wild collection), reef-cured wild, dry rock + bottled bacteria (cheapest, but slowest cycle). Plan 1-1.5 lb per gallon for marine setups. Cure new uncured rock in a dark bin for 4-6 weeks before placement; it leaches ammonia + dies-off as it cycles.

How Live Rock fits the bigger picture

Understanding Live Rock matters because it's connected to broader husbandry decisions: aquascaping decisions are hard to undo - plan rockwork + sand bed + flow paths before adding livestock.

Browse the Fast Aquatics care library for full husbandry tutorials covering Live Rock in context.