Growing sedintary hitchhiker bothering Zoanthid

[SlackJawQuickDraw]

I have an interesting hitchhiker I would like to identify. It has been growing here along side this zoanthid and sponge. Originally when I placed the frag I had dipped, brushed and thought it free of all but the sponge which I decided not to bother removing. However a few months later noticed a fan filter up between polyps. Thought it was a little vermertid, removed the shell and glued over. I've done a few dips with coral rx as this coral has had signs or irritation. Over the last 8 months it's progressed into this specimen; and I would just really like to know what it is.

It sends out fans like a barnacle maybe? Is it possible that's the cause of zoas irritation?

 

[vetteguy53081]

I have an interesting hitchhiker I would like to identify. It has been growing here along side this zoanthid and sponge. Originally when I placed the frag I had dipped, brushed and thought it free of all but the sponge which I decided not to bother removing. However a few months later noticed a fan filter up between polyps. Thought it was a little vermertid, removed the shell and glued over. I've done a few dips with coral rx as this coral has had signs or irritation. Over the last 8 months it's progressed into this specimen; and I would just really like to know what it is.

It sends out fans like a barnacle maybe? Is it possible that's the cause of zoas irritation?

Other than what looks like sponge, pics are fuzzy and dark from heavy blue lighting