I’m new to Saltwater Aquarium and have a question about algae? In the pics attached shows my live rock in the DT. What I’m wondering is what kind of algae I have. The thick darker burnt red color algae started out as a reddish maroon color and has to be scraped off and comes off in little sheets. What kind of algae do I have? Is it good or bad? The tank has been up setup and running for about 3-4 months. The first pic is what it looked like after about a month. Any help would be greatly appreciated.