That is a very good question. In my experince I have found it is better to be very patient with a reef tank. (I hate it too) If it were my tank I would add the live rock, and let the tank stabilze. It is my understanding that it is best to add the fish slowly at first and let them get stable in the tank, then add the corals. What happens (my opinion) is that each time you add a fish the tank goes thru a mini cycle. Corals dont like any cycles at all. If you just have to add a coral, I would add some green star poloyps or some green mushrooms. They seem to be the hardiest I have found. Even when live rock is cured it changes in a new enviroment, My brain says it shouldnt, but test kits tell a different story. Hope that helps you in some way. Steve