So I have had a pistol shrimp in my reef for about 6 months that I know of. He lives at the bottom beneath a large rock and I never see him come out. I am positive though that it is a pistol shrimp since I have seen his claws and face. He regularly makes the popping noise. My problem is that he is killing all of my snails and seems to be breaking off small pieces of rock. I am constantly picking up the snail shells by his hole. I have read that these guys are harmless, but mine seems to be killing a lot of snails. Is this normal and is it ok to leave him, or should I try and get him out of there? I used to have two and I was able to get the other one out.