which light to use

i just swapped a couple of buds for a 400w hps system. i also own a 1000w and a 250w. i have a growroom decked out with white film about the 4ft wide by 6ft. ive used the 1000w in there before but both resulting plants were males and am now wondering if the heat effected the sex as the last male was more hemi. ventilation is excellent and have an automated watering system. any advice would be greatly appreciated.

plug the 1000W in and leave it running for 2 hours and then take the grow room temp,

I've used 1000W and 250w. I actually prefer the 400w setup (although I use two lights in that configuration). Two big reasons for me is the cost (power) and heat are more excessive with the 1000w. My understanding is the light spectrum is different with the 1000w vs. 400was well ( I don't know that for a fact to be true though). Whether the gender is affected by heat would be news to me.

stress can create herms, but genetics dictate whether it is male or female