Hey I have a dark brown algea just started showing up on my live rock, looks almost like a rust , just wondering what exactly it is so I can decide how to move forward . It’s the darker little patch above the hermit
Nuisance Algae ID Guide. Red Slime, Cyano, Cyanobacteria. Green Film Algae, Film Algae. Green Hair Algae. Green Turf Algae. Bryopsis pennata and B. plumosa. Bubble Algae, Valonia. Lobophora. Blue Green Cyano.
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Looks like new tank uglies. use a toothbrush and syphon it out.