Oh and if what I'm hearing is that you are in a sort of emergency situation where you don't have enough lights because your bulb burned out and you didn't have a spare, that's why you should keep a bunch of CFL lamps around... one or 2 day/night cycles under flouros isn't going to hurt your plants as long as they get SOME light and the schedule does not change.
stinkyattic Reviewed by stinkyattic on . 250watt bulb to a 400watt ballast What happens when you use a 250 watt hps bulb with a 400watt hps ballast i have a self ballasted reflector thats 400watt and i put a 250wat bulb in it and it lit up for 20 minutes until i shut it off. Is this safe? Rating: 5