sarcophyton question

i have a small yellow toadstool leather and in recent weeks i've noticed the polyp extention has shortened, the "crown" and base have remained the same size. i've tested for the usual water parameters and there is no change, my bulbs are also only about a month old. the only other bit of information is that i run chemi-pure but should still have another couple of months to go. is there something i'm missing? what else should i be looking for? thanks in advance.

 

Just leave it alone, My closed up for a week, when I first put it in the tank, and sometimes it doesn't extend fully, or close up for a day at times. If your water parameters are good I would worry! I seen other's that their's closed up for weeks, but eventually open up.