Watering times, and timers for aeroponcs

I was just wondering if anybody had any good watering schedules for aeroponics systems, I read in one place for 4minute on 2minute off, but I'm wondering is that 24/7? because finding an electoric timer that can do that is getting annoying without dropping 200 bones on it. so does anybody know of any good timers for their gardens? some lighting schedules would be nice also if anybody has any good paterns. thanks...
~aerohopes

I'd do one on, four off. All day, everyday.
Some here have theirs spraying constant , no off time.

Good Luck!