Thanks for the input. My plan is to use a 6 inch for intake, and a 10" for exhaust in the room. I read you should use a fan at least 1.5 times the intake for the exhaust. I am tying into an 8 inch duct pipe that is already attached to roof vent. House is 2 story and no close neighbors, so my odor probs should be addressed.

My 1000 watt HPS's have the sealed hood. I will be bringing in fresh air with one vortex, blowing thru both, and exhausting into same roof vent pipe with second vortex fan. So my heat should be controlled also.

As for bulb choices, I can use either if I feel I want to experiment. My lights have digital ballast and will run either, plus they use less juice. Little more in the beginning, but they will pay for themselves over time.

I like the idea of the added CO2 from the veg room. That is something I will think over and seriously consider.

Thanks again,
b0nger