I have a set up with a 1000 hps, and its just too hot i cant sem to be able to get the temperature down, i have a ventilated system but its still very hot ,
so my question is can i use a 600 watt bulb on a 1000 watt balast?
Can you? probably.
Should you? absolutely NO! - the bulb and ballast should match (both wattage and type: MH or HPS) otherwise you are risking electrical fire.