I have a growing black algae problem. I posted pictures in an earlier post (June 20th). At that time there were not a lot of spots and they were confined to the deep end about 5 feet down. I was keeping the FC at 7-10 during that time, and yes I messed up a couple of times and let the FC drop below the 7 minimum, but never longer than a day.
Since then I have tried to keep the FC to at least 10. I have tried the vitamin c with no effect and the chlorine tablet with no effect, although it was difficult to do anything 5 feet down. I bought a wire brush and have brushed some but it doesn't seem to do anything.
Now, the black spots have spread. The original area is 2-3 times as wide and longer and there are mo0re spots in other areas.
So, what do I have to do to get rid of this BA? How high does the FC have to be and for how long? Does the pH matter?