no idea what this is on my live rock. think it snuck in on a bit of lr or with some corals but i checked all me coral b4 hand, is it a coral? is it an invert? it kinda hides and then opens up been in the tank now about 2 weeks.
Yeah, looks like a feather duster to me. You're lucky to have one with such great color. I saw a blackish blue one in my tank, but it's on the top back side of a rock, so you have to really be looking to see it