Help with strange growth

[mate209]

Hi there guys. Just had a question about this growth on my ring of fires. I outlined it with red. None of my other frags or colonies have this only this frag. The black growth (maybe a sponge) does have little holes like mouths. Also in the infected zone you can see that one of the polyps is actually turning black maybe infected?
Should I just frag a couple of clean heads off and toss the rest? Or try cutting it the black growth.

 

[mate209]

Also I teied to color correct it so my apologies in advance.

 

[mbingha]

Looks like a sponge to me. I wouldn't frag the zoas, rather I would take some tweezers and remove as much of the sponge as you can, and then dip the zoas in something like coral Rx, revive, or the like.