Elegance coral algae?

[BraindeadBiologist]

I noticed this sponge like slimy algae on the skeleton of my elegance coral. It doesn't seem to be harming but it is spreading. Any idea if it's something I should be concerned about?

 

[WheatToast]

Do you have pictures under white light (ex. With a flashlight)?

 

[BraindeadBiologist]

Do you have pictures under white light (ex. With a flashlight)?

Yes

 

[Holst]

Looks more like a sponge to me.
Soft toothbrush and brush it off.

 

[BraindeadBiologist]

Looks more like a sponge to me.
Soft toothbrush and brush it off.

Thanks! I was thinking the same since it doesn't seem to spread fast or cause much harm

 

[WheatToast]

Sponge. I have a similar one that hasn't harmed anything, though it has become very large with time:

Tan sponge: