Snapping sounds in my tank

[Canadian]

There are a number of things it could be. Mantis and pistol shrimps get blamed most of the time. But I've heard similar noises from clown fish that will making a snapping sound with their jaws from time to time. Additionally, I discovered earlier this year that blue leg hermit crabs can make similar sounds as they attempt to violate each other for their shells. I was sitting by my tank and heard that dreaded clicking sound and jumped up to see what it was. I discovered it was a hermit crab violently tugging on another crab trying to evict it from its home and hitting the shell on the glass of my bare bottom tank.

[Eyford01]

maybe check out some cheap diy mantis and crab traps just in case, leaning a glass jar with bait on the bottom against a rock for the night might catch the gorilla before it causes any (more?) damage, also i had a HH pistol shrimp, he would snap sometimes several times (up to 5 or 6) about a second apart but never caused any problems, only ever saw it twice just heard it lots

[Toolman]

The three fish I lost were all smaller, I also have an large anenome crab as well that I just added. Could he be the culprit ?? Maybe I will throw him in the sump and see what happens ??

[Toolman]

I found the carcass of the crab with one very LARGE claw and the snapping has seemed to stop, I don't know if it was the large anenome crab that got him but if he was the culprit then good riddance...........