1st Grow hydro set up under my stairs

i am germinating lowrider - master low seeds id like help and some advise on my set up PLEz help :P i have posted some pics of my room

i put mylar over every inch of the room it is seald with a tall osilating fan and a small extraction fan in the bottom left corrner my light on temps are high 32* - 35* lights off range from 19* to 22* i am going to buy a carbon filter with a 4" can fan for extraction the room is 3'Wx3'Dx3'6' high and 30" from the top of the rez to the 430 watt HPS should i go air cooled reflector hood or should the 4" extraction fan do the trick and i am also wondering about how much yeld you guys think i will get with the light i have and 6 low riders-master low I am also wondering if i could put some poted plants into the room also and how many do you think i could fit? with the 430 watt HPS