Trying to identify something...

[Amantijt]

So have a hammer and it’s always had some “dark spots” figured it was some discoloration of some sort. After tonight looks like it has spread ALOT since I’ve last paid attention to it. Might someone know what or why there is some blue Something growing around my hammer? Got the best pic I could. It was maybe 1/4 visible a few months ago and now seems to be growing/spreading on this coral alone very steadily. Should I be worried or leave it alone? Lmk thanks

 

[ScottR]

Most likely just a black sponge.

 

[reef lover]

+1 sponge. That variety there tends to be a bit aggressive I would personally remove.

 

[Amantijt]

+1 sponge. That variety there tends to be a bit aggressive I would personally remove.

ok thanks

 

[Amantijt]

ok thanks

best way of removal?

 

[ScottR]

best way of removal?

Take it out and scrape it off if possible. Sponges are quite easy to remove.