Need Help with ID

[savageAJC]

besides that alien species growing on it, thats a nice red rock!

 

[Bifferwine]

besides that alien species growing on it, thats a nice red rock!

Oh god. Take it!!! Every rock in my tank is covered with this soft, velvety maroon algae. It's not cyano, it's not diatoms, it really feels like velvet. Some people have said it's a type of coralline, some have said it's an algae that grows only in low-nutrient systems; I have no idea. All I know is that my tank looks like a cheap Vegas motel room. You can see the white patches where the urchin and tang feast on it. They both love the stuff. Unfortunately, I'd need about 30 more tangs to take care of it all.