New member
The rocks I have placed on the sand have a habit of moving during the night. Some of these are rocks half the size of a mans fist and the have moved as far as 15 inches.

This morning I awoke to 3 corals shoved together. My large open brain was angled upwards with another coral underneath it and a small frag of Acan shoved to the side of the pile. It was an expensive gooey mess. I shone my torch into the mess. No critters in there but a clicking came from the tank.

Is this the work of a Mantis? Are they capable of moving such relatively heavy rocks? Any other suggestions as to what it could be?


New member
If it was a mantis, it would have to be big enough to move those rocks. Keep an eye out for the culprit, but you definitely would have noticed it. Nor have I ever heard of a large enough species of mantis to do that hitch in.


New member
Pistol shrimp could do it but you would have seen it by now. I have seen my 5" hippo tang move rocks out of her beding area with her mouth. The largerst of these was 2" across. If I move the rock back she moves it farther away.


Go Buckeyes!
Premium Member
Get a red flashlight, turn the lights out, awhile later place some sinking food in the tank... and see what turns up.

Good luck.