Just wait, in a few weeks the green will start to show with all your lights on... it's appearing under the actinics so it's just a matter f time...
It's really funny how it settled right where I thought it would... You'll know for sure in a few days, once it is settled if it really likes the spot. If it likes it, it won't move.
I didn't purposely feed it when it was in my tank, but I did have the clowns in there - maybe they fed it. But both clowns had died a few months ago and it was doing well under the 250MH. It won't hurt to give it something (like mysis or small bit of fish) though in a few days. A good reaction would be the food attaching to the tentacles and drawing it up to the mouth. You'll know you've fed too much if it later spits out a glob.