To give a little history, I have had this 90gal going for 3 years and after 2 years of hard work, a lot of money, and a lot of patience it looked absolutly gorgeous, but I got real busy with my job and kinda let it go downhill until about 2 months ago I started trying to repair it. I had lost a lot of beautiful corals, but anyway I have this hair algae problem that is not wanting to go away and I thought maybe a little carbon might help clear it up, though I have never used any before.