I just discovered what appears to be a little baby starfish climbing a leaf in my tank. It is smaller than my fingernail on my pinky finger. Has five legs and moved more than an inch in a couple minutes. I have a common star in my tank and about 50 lbs of LR. I guess it could have hitched a ride? I would post a pic but its so small I can't get a good shot. Any guesses what it could be?