What is this critter?

[verniedlx]

I have this thing tangled in my one of my paly's. You can only see it when the paly's are closed.

Any idea what it is?

 

[Esmond]

Looks like a tubeworm to me,but im not sure.

 

[verniedlx]

There are a bunch of them all tangled up, and they dont move really...

 

[Gesiggie]

They look like feather dusters.
If you move something close to them, do they retract?

 

[Jayceew]

Agreed Feather duster, filter feeder. They can take over a tank over time but are soft and relatively easy to remove from the rocks.

 

[RiaanP]

nice filter feeders.
let them be. Unless they are really taking over.

 

[Helga]

Ooh my Copperband goes crazy for them. They took over some of my liverock in my previous tank and he decimated them within days!!! Its his favourite food...

 

[Dawie002]

My copperband also loves them. only place where they take over now is the sump