Worm on live rock?

[LaWoWee]

Does anybody know what this is? It looks like either a worm of some sort or an arm of a brittle star..

 

[Reef Mechanic]

Looks like a bristle worm to me.

 

[LaWoWee]

Thats what i thought it might be. Im kind of new to this. Are they bad to have?

 

[David S]

they are a good part of your CUC but if you have too many then your overfeeding.

 

[lbannie]

watch your fingers around those things, they sting you and it feels like itchy splinters! I have a bunch in my tank!!