When I first got this coral it would not open to eat and then I found out if you use a turkey baster and kind of let some juices from what ever food your using(I use frozen mysis shrimp and home made mush) flow over the polyp then they will start to open up!
I found out the more you feed them the more they will open up and are really pigs too! They are more apt to produce buds if fed more frequently which is what I am hoping for! HTH
Mine doesn't have any problems in opening..it will stand tall and proud, and I do use the baster. But when the food catches on it's tenticles... nothing...it doesn't close up anymore around the food. It just sits there. When I come back later, the food is still in the cup. I even used tweezers and zooplankton and hand delievered food to each polyp and nothing.