I bought two firefish yesterday and put them in my 30 g reef. They seemed healthy and active yesterday evening. THis morning they seemed to have vanished. I checked all over the floor and I doubt they could have jumped because I put a plexiglass lip over all sides of the tank. Is it possible that they are "sleeping' in the rockwork somewhere and aren't coming out? By the way all I have in the tank other than them is an ocellaris pair, some hermit crabs, and lots of sps and lps.