I want to upgrade my grow room with 400 watt or 250 watt HPS light. Heat is a big concern for me. I live in FL the temps are very high. My grow room is a 6x2x10 space, but i will only grow in 2 or 3 feet of it, but I have the entire space to use for the dispersion of heat. I'm looking for quantified answers or applied practical knowledge (i.e. "I used a 250 watt in my 2x2x8 room and it raised the temp by 15 degrees w/out ventaliation). I have the following questions: 1. How much heat does a 250 watt bulb emit? (how many degress does it raise the room. How much heat does it emitt per sq. ft.?) 2. How much heat does an average reflector add to the heat of a 250 watt bulb? 3. How much heat does a 4000 watt bulb emit? 4. How much heat does an average reflector add to the heat of a 400 watt bulb? Once again, I'm looking for quantified/applied answers. Everyone should know the demensions of their grow space. Everyone should know the temp of the room w/ and w/out the lights on. Please let me know what size space you grow in and how much the temp it raised w/ out venting the air Thanks guys.