Has anyone had a hermit (or pack of hermits) and/or a scarlet cleaner shrimp that liked to move small rocks around the tank?

I have some new zoanthid colonies on small rocks and i have noticed they tend to move around the tank. The fish (two small clowns and two cardinals) are too small to do this, leaving the cleaner shrimp (2) and the scarlet hermits (about 7) as the suspects. At first i thought it might be a mantis, but i have not seen any hermits go missing recently.

My hermits move frags around by walking over them.

i have not noticed it since i went exclusive to snails, but know that you mention it ... my smaller frags DID use to move around a bit. i wonder if it was the crabs ??!!