help Space problem!!

ok i need help i am about to get 2x1000hps/mh with normal open reflector setup for 32 fem big bud but my pots are one foot tall and my maximum to ceiling height is 5foot7 my room temp flows aorund 23deg i have a heater to help with temp in case with lights its not enough but im thinking maybe the plants will grow too tall and touch or be too close and get burned or should i go cool tube instead ?????? im not looking for massive plants but i wanted 4foot ones, and does big bud double in size from veg to budding????

pots are a foot , consider the light and reflecter a foot so u got 2 dead feet so far, then alwase with 1000w hps or mh i would say ul need about foot and a half MINIMUM inbetween lights and plants... so theres 3.5 feet... leaving 2.7 feet of plant growth ,...... now in flowering they will double or triple in height so..... ul need to flower al like a foot tall make sure theres no light leaks , and without cool tube im bettign its going to get to hot ... 1000w get stupid hot man and have a good ventilation with inline fanleading outdoors over a short distance too....