I usually rinse it off first, but it does not require cureing for months like fresh uncured live rock, and no risk of adding unwanted parasites. As long as you have a few pieces of live or a few cheap corals, the color and life will spread to the new rock within a coulple of months. You would normaly have to wait this long just to cycle uncured rock. Honestly the stuff most wholesalers are selling as live rock now days is pretty foul. They really have no business selling rock as live that has been sitting on a ship in the ocean for a month or more, and in their wharehouse for another week or two. If you have a few minutes I will tell you the whole story and history of live rock. Give me a call or come by the store this weekend. I will be there Saturday and Sunday for rock sales.