I think there was too much flow in the tank. I would feed my dendros and micros/acans almost daily, but this little guy wouldn't open up. Sometimes at like 3am he would be partially open, so I would try to feed him, but not much luck. I think there was just too much flow in the tank, so he began receding from lack of food.
Oh well. They're cool corals, just like zero flow and lots of food. I think they may be nocturnal too, so you'll have to "train" them to open up during the day.