Can't tell anything from the shaky hand holding the camera. Take another [longer] STEADY shot and repost.
I have watch the vid - about 10 times now, but I still can't make it out - maybe if you can get a better pic looks a bit like a head of duncan coral... but not sure that is it... hard to see
It isn't any coral. Looks like a worm of some sort but if you get a good look at it and it has tentacles on the head end of it it could be a eunice worm. Just use a red lensed flashlight after lights out and you should be able to get a good look at it with out scaring it off. Then you may be able to give a good description of that thing. Its hard to tell in the video.
I am with Grimmett. Its a form of worm (cant remember the name) sort of like a feather duster. Its a filter feeder and at night will extend these long clear tentacles out and feed. They are no harm to the other inhabitants, I have quite a few of them in my tank. They are very common. No worries.
ok thanks guys I have had that rock in my tank for about 5 years now and I seen it one night. Its hard to get a good shot of it. When I go to the tank to get a look I don't know if it's out till it moves back in the rock
