I got one on my original live rock, he was about 1/2" in diameter, and brownish....haven't seen him in months though. I DO wonder if he's the one that decimated my green star polyps... Just put in a new live rock, came out of the display tank at my LFS, and was being "stored" in their coral tank, and found a BUNCH of little blue-ish looking stars on it. They look like Asertinias, but are more of a light blue. I hope they stay away from my Xenia's....