I'm still constructing my room ventilation setup, also with a 6" inline blower and a carbon filter. The previous post is correct that the carbon filter should be on the opposite end of your diagram (suck instead of blow). I would also keep your light cooling system separate from your temp/filter exhaust system, but this might depend on how much space you have for your grow. I have a 10x10 room, which gives me plenty of room for air circulation and an exhaust system, but a small grow tent might be a different story. How much space do you have to work with?