sick leather ???

[30_gallon_guy]

I have a 35 gallon tank with 2 36 inch florecents, one powerhead and my skimmer. I have about 20-25 pounds of live rock. I have one colt coral that is thriving and growing alot, i have a candy cane which also looks great and is growing new heads. my only dilema is my pink finger leather. Iv had it for about 4 months and it is growing but for the past 3 or four days it is slumped over on the rock. During the day the polyps are open but it is still slumped over on the rock. (its mounted to an old snail shell) At night the polyps close up and it shrinks but still slumped over on the rock. its as if it cant stand up strait anymore.

pleas any advice or suggestions (btw when you touch it lightly the polyps close then open again)
thanks