I feed all of my fish 2 times a day. Once in the morning about an hour after lights on and once in the evening an hour or so before lights off. However, they don't get fed on Saturdays. I chose Saturdays as an off day since if I go out or something it's Friday night/Saturday. My water parameters stay perfect with once a week with 1/3 water change. Sometimes if I have spare time through the week I'll do an additional water change just for the heck of it. Everyone seems happy and they know their schedule. 
