Sebae doing something odd

I have had my tank for a couple months now.. my large sebae clown has just started tail fanning two LARGE holes in the crushed coral within the last couple days. It is acting very odd with the holes. Like rubbing sideways against them. It sleeps in these holes as well. Not sure if it is making itself a bed or a nest? These holes are quite deep. Is this normal behavior or could it be making a nest? Another piece of info is that is has been eating quite a bit more aggresively lately as well. Nothing has really changed in the tank. I took my anemones out a few days ago but it wasnt hosting one anyway.
Any ideas?

 

my maroon does this with my fine grain sand... annoying as hell. Seems normal to me, has been doing it for about a year now.

 

my maroon does the same. I figured he has an itch.

 

Cool Cool.. just wondering because it never did it before and I was kind of hoping it was going to lay eggs lol. I do have two clowns, one regular clown and that bigger sebae but dont know if they can crossbreed like that.