Even though you purchased "cured" rock, you may still have a small re-curing time after you recieve it especialy after it was shipped. This will be a much shorter cycle time than curing rock that has come direct from say Fiji uncured because they will have cleaned it up quite a bit, but I have still had cured rock do a small cycle in my tank. If you got it from say your
LFS cured, then most times it is cool just to drop right in...
