I have a shrip in my tank that came with the live rock. I'm not sure if it's a pistol shrimp or mantis shrimp, but, it's killing all my snails and hermit crabs within a month of when I get them. I need to get rid of this preditor. I think it's a pistol shrimp becuase of the clicking sound it makes in the tank. Does anyone have any suggestions on how I can trap or kill this nasty shrimp?