My rocks were looking great until recently I noticed all my coralline was being covered by a thin layer of brown algae. my 46g fowlr
has good water quality except nitrates are at 25ppm. I do a 15 percent water change every week. I treated my tank for red slime, which is usually easy to irradiate but I quickly found it was not going to be that easy. I am wondering if maybe a recent light upgrade created this problem . Any advice on getting rid of this algae would be greatly appreciated.