Ok,
I have had my tank up and running for about 6 months of something like that. 4 months ago I put a pistol shrimp in the tank. I have never seen it since, and I made a major mistake about 1 month ago and got my tank up to 93 degrees for 2 days. Killed every invert that I had. However, I keep hearing that snapping sound that pistol shrimps make. I suppose he could have somehow been the only invert to survive the heat wave...but it seems unlikly since he was BY FAR the smallest invert I had. He was only about 1/2" when I put him in the tank. Does anything else make that noise? Would an emerald crab be able to snap like that?