My starfish has been hiding for several days. When he came out yesterday,his arms were all chewed up. I thought maybe he got caught in a powerhead, but today his arms are even shorter.
Just added about 10 lbs of live rock, is it possible a hitchhiker is responsible?
Unfortunately with these types of stars once they start deteriorating it is usually over for them. Nothing is eating it, they tend to just start disintegrating after a short period of time, usually due to starvation as their general diet is not well understood.
As others have mentioned this isn't a sign of them being eaten. It's typically a sign of their inevitable death. I'm not sure I've seen/heard of one coming back once they start deteriorating like this. It's really a shame as they're such beautiful creatures. I had a red fromia myself and was able to keep it for about a year, but ultimately the same thing happened to it. These are creatures probably best left in the ocean in most cases until we have a better understanding of how to properly care for them.