It looks like waving hand anthelia, I have alot of it in my tank good luck and a word about it, it grows like a weed you will be fraging it all the time.
We were told it is pulsing xenia...but often called pumping or waving. I'm a little worried about the copperband butterfly...he's been investigating the rock it's on but so far no damage...we're watching him like a hawk though.:doubt: