With the new controller you can operate one set of lights on one tank and then switch to a second tank and have a totally different schedule. The new controller does make it easy to do.Ok I had one small question that I'm sure you would know the answer too. If I buy multiple lights for my tank can I set each fixture to a seperate light schedule, or do all tanks using the same controller have to use the same settings? Sorry if it's a stupid question but I know almost nothing about these lights.