i have a 400w hps mech ballast & im thinking of moving up to a dimmable 600w digital ballast, i'm curious how much more heat the 600w bulb will produce over the 400w? i have my setup tuned fairly well with my 400w, i run mid to high 80's on temp, with all things equal(ballast is outside of grow area) will the 200w extra bulb cause me to have over heating problems. i am thinking of getting a 600w dimmable ballast that way if i run into heat problems i can dial it back to 400w to what i know is running good. ive noticed if i get a lumatek 400w digital, it has a super lumen setting that will allow me to push a 400w bulb harder. which im curious about the dimmable 600w ballast, the knob that allows you to change wattage, do they have a detent that clicks in at 400w & 600w? or is it infinitly variable? thus allowing me to also over power the 400w bulb, similar to the super lumen output? just a lil info on the setup its a 2x3 foot closet that has 2 plants in dwc in it. they repeatedly are producing about 10-11 oz every 8-9 weeks. will an increase in wattage make more of a larger yield or denser buds or quicker maturation or maybe all? i'm curious if trying to raise my wattage is even worth the trouble, i am buying a new digital ballast either way, im just not sure which i should get. any thoughts or experiences? thanks guys this site rocks!!!!