I bought a piece of "christmas tree" rock that has the little "paired" feather dusters all over it, but I have noticed 2 other critters that I am not sure what they are. I've had the rock in quarantine for about 5 days now and want to introduce it to my tank but cant until I figure out what these guys are. So far I've seen 2 of them and they look black and white banded legs coming partially out of the hole. kinda like 3 octopus legs with spikes or hairs on them. They dont look harmful, they just lay there and almost look dead the way the ends of the legs float around in the current. I've looked all over chucksaddiction and did a search here but haven't come up with anything yet. Any ideas what it could be?