I have what's getting to be a serious infestation of black brush algae in my 10g. It started on one side of the tank where I didn't realize it was getting about 30 minutes a day of direct sunlight. The java fern on that side started growing it along the edges and now it has spread to my crypts in the same area and it's growing on the wall, and now it's getting to my hygro, and it's also on the other side of the tank now too in smaller tufts. I blocked the sun from that side and I'm going to step up my water changes and fertilization (lately it's been about every two weeks), but how do I eradicate this stuff besides doing what I'm doing?? It's a non-co2 tank with 18 watts of light. Excel is not an option, I can't get it here and it would cost me a fortune to ship it in.