Need help ID Algae

[MrZ3no]

This algae been growing on my rock and back of the aquarium for the past couple month… it killed a lot of my zoas and mushrooms by covering it. I just don’t know what to do. I use chemi-clean couple month prior… I don’t know if that’s the reason why I got an outbreak like this. I don’t even know what it is to be honest. It’s like a reddish brown hair algae and on the sand it’s like a reddish stuff.

 

[Euphyllia97]

Looks a bit like cyanobacteria?

 

[NonstopSoda]

could you post a pic under full white lights? It looks like a combo of GHA and Cyano from what i can see