So I recently got a flame scallop and it seems to be receding into his shell. I’m worried he may be dying there are no nitrates and my calcium is at 400. Everything else in the tank is thriving. This morning I found two of my hermit crabs picking at the scallop and the scallop actually closed one inside it. Are these crabs eating my scallop? How do I safely open the scallop to get the one crab out?