I have had a mantis sneak into my reef before from live rock and corals but he made himself very present by showing himself and and showing hostile displays to every other fish and shrimp in the tank. He never stayed in the tank long enough for me to watch him feed but I hear they are quite loud at it. Now when I turn my lights off I hear a series of loud poping for 30 - 40 minutes after the lights go out. Im not sure but could I have a more seclusive mantis ? I have lost all hermits 1 tri. clam and 50% of my snails. The only fish that has disapeared was a small sail fin. All water param. are fine? I was just checking with you guys to see if you would know.