Yes,most corals feel more comforble on the bottom of the tank with sand.And make sure a good stream of water hits it.The same thing happened in my tank with a brain coral and it helped so much!It was better the next 48 hours.But if that doesn't help,you may need to start putting "Coralife" liquid in your water to feed it.It may be deciling because it is starving.Better yet,after you turn your lights off,put a frozen cube,unthawed enough that it has very little ice on it,and stick it in the center of the coral.Then do not bother it for a couple of days.Contact me again today to tell me whats going on!