Is this a barnacle??

[bkushy]

These zoas were doing great and all of a sudden aren't opening fully. Always thought it was a barnacle and harmless but am now wondering if it is something that is harming them.

 

[Bige]

It looks like a tunicate. Hard to tell from pic. Does it open and close on the end? What happens if you touch it? Could be a few different things.

 

[Bige]

And tunicates are good filter feeders. You could probably pull it off. Gently.

 

[bkushy]

It does open and close. Nothing really comes out of it just an open hole. Would it be growing and affecting the coral?