Need help identifying this sponge/algae and help getting rid of it

[bradymoloho]

Long established tank, this one rock has development this green algae and the other some kind of black (algae? Sponge?) what are they and how can I get rid of them? Root cause?

 

[EnterName]

Green algae might be a green cyano species. Is it slimy and can be blown off the rock with a turkey baster/pipette?

The dark/black "algae" is very likely a sponge. I had to nuke a rock that had such a black sponge as it grew around zoa heads and "choked" them to death, but I'm not sure if all dark sponges are causing trouble. Usually I like sponges but if they grow fast/aggressively or seem to bother corals they get thrown out.