How to Cure Live Rock
Along with advances in technology, the use of live rock has been one of the methodologies that has lead to widespread success within the saltwater aquarium hobby.
Live rock comes from tropical regions around the world. Its porous open structure allows the rock to host a wide array of beneficial bacteria, micro and macro flora/fauna as well as provide a stable base for coral growth.
Because the organisms found on live rock will quickly begin to die once exposed to air, it is always advisable to cure the rock before use.
Curing un-cured rock may be done inside a plastic bin or inside a newly set up aquarium. Curing live rock inside the aquarium is preferred but a large water container is a suitable alternative. Do not place substrate inside the tank or water container during the curing process since this will further elevate nutrients and lengthen the curing period.
To cure live rock properly, you’ll need the following equipment:
- Protein Skimmer A protein skimmer will remove organic waste from your aquarium or container before it breaks down and creates ammonia.
- Powerheads Using a powerhead (or two) to create ample water flow is key to properly curing live rock.
- Heater Set the heater to 78 to 80º F. The bacteria and organisms found on live rock thrive in the same temperature range as the fish and corals you’ll eventually be adding to the tank.
- Lights If you are curing live rock inside your aquarium, limit lighting to 4 hours per day to reduce the occurrence of nuisance algae.
Perform water changes as need. We recommend larger than normal water changes during the curing process—20 to 30% every few days—although once per week is still acceptable.
Siphon off all the dead debris you can find. Pull off any dead sponges, plants, etc. Do not scrub live rock unless you see obvious dead areas on the rock itself. During the curing phase, monitor the rock for signs of nuisance hitchhikers, like crabs or mantis shrimp. They are easier to catch and remove before you’ve meticulously arranged (and possibly epoxied) the rockwork in your display tank.
Perform Ammonia and nitrite tests frequently during the curing phase. You will know the live rock is cured once the ammonia and nitrite spikes have ceased. If you are testing regularly, you notice these levels dropping rapidly to zero.
You may also perform a “sniff test.” Cured live rock has a fresh smell; if your rock has the aroma of rotten eggs, you know it needs more time.
Limiting lighting while controlling ammonia and nitrites should cure your live rock in 2 to 3 weeks. Your new aquarium will benefit from the healthy colonies of algae, plants, corals, copepods and other organisms you've nurtured during the curing stage.