is this Zoa fungus or something else?

[snowlynx]

Do I cut it out? Leave it alone? Just don't want it infecting rest of the tank.

I have dipped all in seachem reef dip before putting in display tank

Few zoas are getting like this. I did frag it from main branch, there were
on the back of the branch, pressed against the rock and hidden from view
so I fragged to hopefully get more

 

[mcgyvr]

Likely a sponge..
The sponge usually wins too.. Pick off what you can.. Hope for the best..