Feather duster look alike

[keddre]

this think looks like a feather duster, but it has larger gaps. When I poke it with a stick, it only withdraws halfway, instead of fully
Edit: believe it or not, this is the best picture I can get

 

[Maggie321]

Could it be a barnacle? Look them up. I have one in the middle of my candy cane coral. Looks similar...

 

[keddre]

Could it be a barnacle? Look them up. I have one in the middle of my candy cane coral. Looks similar...

I was starting to think hydroid. From what little I know, barnacles are constantly flicking in and out their shell. This thing is sitting open constantly

 

[KJ]

Polychaete Flabelligeridae.

 

[keddre]

Polychaete Flabelligeridae.

That looks like it and appears harmless. Thanks

 

[KJ]

That looks like it and appears harmless. Thanks

YW