i discovered this odd looking thing on my fiji rock today it looks just like the rock and looks like a shell like thing that opens and it also seems like it has a beak on the front end. its really hard like rock and moves up and down slowly from a gap in the rock. i tried to feed it a brine shrimp like coral but no response.
i really want to know if it is a threat for any of my inhabitants.

i really want to know if it is a threat for any of my inhabitants.
