What's wrong with this elegance coral?

[asylumdown]

Anyone know what could make an elegance coral go from this:



To this:



?

I've had this particular coral for well over a year, it was previously in my pico tank, and was one of the first corals in my big tank. It seems to have totally lost all it's tentacles, and the body has since bleached. Nothing in the tank has changed, other than the addition of fish (it was fishless for several months). I've seen my Doliatus rabitfish picking at the elegance, but that didn't start until well after it had deteriorated and the tentacles had melted. It went from the first pic to the second in the span of about a week, and has been like that for 2 weeks now.