Well I guess I`ll be the first to post a pic of christmas pick ups. My daughter got this orange seastar for my reef tank. I had a blue linknia that I had for over 4 yrs but have not seen it for a few months now. Oh well here he is. Sorry for it being kind of fuzzy.
Disintegration sounds more like a voltage leakage problem. I had three linkias that had that happen to them before I figured out my powerheads were leaking voltage into my tank.
it could have been nitrates too, this was a long time ago, but the guy at the pet shop said that that specific type of sea star, not other types just that one and the blue ones will disinegrate under higher temps :0