Sorry for the blurring pic, but it's the best I have for now. For a while, I have noticed this red growth all over my rocks and back wall of my aquarium. When doing some cleaning inside the tank, I noticed that it is like red velvet. The only way for me to remove it is with something that can scrape it off. I'm only bringing it up now because my coral and fish all are doing well. Has anyone experienced this type of take over? And can identify what it is and what causes it. I've heard from my lfs that it may be water quality from RO/DI and changing the filters and media would help. It hasn't. They also mentioned that it can be a nutrient imbalance; but with no help on how to clear it. Help on this would be greatly appreciated. Especially if this can be detrimental to my tank.
Thanks