ID: Dark Brown Algae

[GoFish]

So i have this dark brown algae growing on stuff, cant seem to find an ID for it. Not casuing any problems that i can see but would rather see coraline if anything. Its really dark and has a bit of a slimy feel and is firm. I can scrape it off with a knife, but it cant be brushed off

An ID would be much appreciated, or even advice on how to control it. If any tank parameters are needed just ask

Thanks