what is this on my Torch skeleton

[AandR]

ID help? something to worry about? Noticed this greyish "things" on torch skeleton. ??

 

[Troylee]

Looks like a sponge.. if it’s black you need to get rid of asap as it’s invasive and will corals

 

[Goaway]

I don't know if it's a sponge of a tuff of algae, do scrape that off though.

 

[coraler07]

I think I had what you have, def a type of sponge but forgot the name. Easy to scrape some off, but hard to get all of it. Harmless though, should be okay to leave