You are still overfeeding. I feed mine 3 times a week, many others including the experts on here do similar and our fish are fat and healthy. The high flow will not stop cyano, just lessen the appearance of it most of the time. over time, the removal of cyano through syphoning it from the tank during PWC's and renewal of good quality RO water assisted by a reduction in feeding will result in a beautiful cyano free tank. you will be able to have your lights on more once the problem is sorted,