Some questions about HPS

My grow area is 14" x 12" x 35.5" (WxDxH) and it will be covered in mylar.
Is it possible to have a HPS 150W in there or will it be to hot? I planned on going for a 200W CFL but having seconds thoughts. But I'm worried about the heat.

- Will one 120 mm exhaust fan do the trick or do I need more than one?
- Does a glas board under the HPS take away lots of heat?


Thanks!

More Exhaust is always better, you way want to stick to the CFLs, you could probly cram more in there with those, than dealing with a 150watt HPS.

the 150HPS are pretty hot, glass traps heat and it becomes an oven unless its air cooled. I used a 150 HPS as supplementory lighting with a plant i set next to my kitchen window to get natural sunlight. that thing got pretty hot. I would be worried about it being in that small of a space, without ample exhaust.

they make 300watt equivelent CFL bulbs now. they look huge my buddy used two of those and 3 200 watt CFL around the sides and got one plant to look beautiful.

I run two 150watt HPS floodlights still in the fixture so the reflector and glass are still there...the glass does help keep back the heat a little bit, but my growing area is 10x bigger than yours, and in an area where the ambient temp is about 60-70F(sometimes 50F)...a single 120mm exhaust fan might be enough to pull the heat out at the top(check the CFM on it), as long as you are replacing the air completely in that small area about every 15 minutes you should be fine. Easiest thing to do...set it up...hook it up without any plants in it...let it sit running for an hour and check a thermometer to see where you stand...if the ambient temp in the room is around 70F and you are holding the temp in the box at 80F you will be fine. I don't use any exhaust fan because my area is much larger

You are going to want to keep the height of your plants to a minimum so I'd suggest either going with a scrog or LST'ing the shit out of it

scrog that sheet

HID lighting produces the best yields, but your grow space is simply too small to be running an HPS lamp. My suggestion would be to use high-output T5 lamps. They're compact, economical and provide excellent intensity in a small area. They run quite cool, too, so you don't have to worry about high temperatures. Check out your local aquarium store to get a better idea of what's out there. There are some great horticultural bulbs available as well, so you can really tweak your color spectrum when using T5 bulbs.

Yeah... I think I stick to the original plan; SCROG & LST, CFL 200W (16.000 lumens).
Thanks for the advices!