Whats this brown stuff killing my zoas?

[BigBabich]

I have this thin brown stuff killing my zoas. It's driven them right off the frag plug. Had them 6 months, they were doing great. I tried blowing water over them with a turkey battery and it wouldn't budge. Used aiptasia-x on a little aiptasia that also started growing in the middle and it melted off the brown stuff (some of it) too.
Any ID? Never seen it before.

 

[vetteguy53081]

I have this thin brown stuff killing my zoas. It's driven them right off the frag plug. Had them 6 months, they were doing great. I tried blowing water over them with a turkey battery and it wouldn't budge. Used aiptasia-x on a little aiptasia that also started growing in the middle and it melted off the brown stuff (some of it) too.
Any ID? Never seen it before.

Pic quite fuzzy to tell but may be sponge

 

[brucey]

Looks like a chicken liver sponge
Will surround and kill zoas more than a typical sponge
You don’t want but difficult to get rid

I’ve found nothing that eats it