What is growing on my leather

[Tyrant]

I just bought this Yellow leather on Friday and I noticed today that there is this black fungus like stuff growing on it. You can see it in the picture on the right side. Does anyone out there know what this is? Will it harm my other corals? Will it go away? Should I take it out of my tank? If anyone can answer any of these questions, I would be greatful. I scrapped away some of it earlier today, but it keeps coming back.

Thanks

[dobejazz]

Did it brush off easily?

[aquawolf]

Welcome to TRT!

Do you have an update on the situation with your coral?

[deep water]

did you try a turkey baster and blow it off. i had some gray like patches and darker spots from what i would say was a die off or shedding like after i got my figi but i used the turkey baster on it once a day untill it stopped and it is huge now.

[ChilisREasy]

i think your zoas are stinging your leather when its fully open