I got a new purple firefish from the LFS 3 nights ago but I have only seen him once since putting him in the tank. Is it common for them to hide in the rock work all the time? I've read that they do well in pairs. If I got a second purple firefish, would that help him come out. I'm a little concerned that he died and was taken care of by the clean up crew, but I have a fire shrimp that I hardly ever see too, so I'm hoping he's just shy.