How long of a pause in lighting during the day is needed to keep alae away. I need to have the lights on at 6:30 a.m. to morning feed and because of the second job they need to be on til 11:00 p.m. for night feeding/maintenance. I have heard that turning the lighs out during the day will kill off algae but the plants can recover, but how much pause is needed? If I have them go out for 2 hrs and come back on is that enough?