Curing Live Rock

  The curing process can be done at home, but often is done at curing facilities in wholesale or retail stores.
"Curing" is the process where wild live rock is placed in a container with seawater and vigorous currents to allow the decomposition of "wild" sponges and other organisms that died due to transit from "the wild" and (most importantly) due to the extraction from "the wild". Many "wild" sponges and other organisms simply cannot survive in tank conditions and they are bound to die... The curing process allows dead matter to decompose and remineralize out of the rocks in an environment OTHER than you tank (because the decomposition process can cause anoxic conditions that may kill your fish/inverts). ALL Live Rock that comes from the ocean (wild or aquacultured) MUST be cured before introduction to an established tank.

Introducing uncured Live Rock to you tank could cause a massive decomposition event ... potentially killing all your aquarium organisms
(learn more about this)

(?)Source: Desertdawg,

Basic procedure to cure Live Rock....

  1. Set up a curing container. 
    1. Add seawater to a bin or clean garbage can
    2. Install one or more powerheads
    3. Install a heater (80oF or 27oC)
    4. Do not add lights (to prevent an algal bloom due to high nutrients)
  2. Remove dead organisms. Use a brush and/or a butter knife to remove sponges, soft corals and other attached organisms that have turned black or appear dead.
  3. Submerse Rock in curing container.
  4. Change seawater every 3 to 5 days. Before each water change, you can do more scrubbing to remove more dead sponges and corals. Then change 50 to 75% of water.
  5. Rocks are cured when they smell ocean-like BUT NOT ROTTEN (ie: no sulfur or rotten egg smell), and when there is no evident decaying matter on the rocks. The curing process usually takes 2 to 3 weeks.

Refining the basic procedure...

  1. (?)Source:
    Add a protein skimmer
  2. Add more powerheads and aeration using an air pump and diffuser stone.
  3. Add lights after the second water change, but don't use high output lights (like metal-halides or VHOs) because this favors weedy algae in the presence of high nutrients.
  4. Test ammonia, nitrites and nitrates before water changes... Rocks are done when ammonia levels are zero and nitrites and nitrates are close to zero for 2 consecutive water changes.
  5. Still do the "sniff test" to verify there is no hydrogen sulfide. Remember rocks should smell ocean-like... and should NOT smell rotten.
  6. With the extra "bells & whistles" the curing process can be reduced to less than 10 days.