Flicking off the rocks

Question
Hi I have a 46g tank which I have had setup for 12mths with seahorses in it but they have passed so we thought we try something else. I have live rock and sand along with some plant that have come for nowhere. I have just bought a 4 striped damsel, its about a inch and half long, eats like a horse, is a little shy but seams fine. After all that I have seen it flick itself off of the rocks, like its rubbing it face against the rock. There is only snails and crabs in the tank with it.
Would you be able to tell me why it does this and if there is anything I can do to help it?

Answer
Hello!

Just normal behaviour. It's there way of escape if they feel they are under attack by some predator...ie) you. Nothing to worry about at this point.

However, you should have a few more damsels in there. They are schooling fish, and should be in groups of at least 6.

Good luck!

-Nick