What's wrong with this turbinaria?

[kdx7214]

So I was given this for free back on Feb 10th or so. I've had it in the tank and it has looked basically the same until a few days ago. There seems to be some sort of white residue in the middle (as seen in first pic). Sorry for the blurry pic, my mom's no better a photographer than I am.

 

[Matt Bravo]

Check parms to start, check salinity. Ensure no large swings have occurred, also ensure other inverts are not eating it (perhaps some sort of crab or shrimp)