my space is about 5'L x 3'6" W x 7' h. had the same problem when i started. this is what i did. fans fans more fans and then just one more for the hell of it.
my temp now is 65f - 70f lights off. 74F - 78f on. before it hit 110. its a 1000w hps
first thing was the hood $110
![light.jpg](/data/attachments/83/83648-878a6511fe6decf2095b9aeea3f41a85.jpg)
a lot like the one someone posted before. i bought a 6" inline duct fan $25 from lowes
![inlinefan.jpg](/data/attachments/83/83649-f55c55f103528457a87a20d072bcd854.jpg)
there is a dryer vent running from hood out the room to the inline fan like this
![vent.jpg](/data/attachments/83/83647-11d6750108ad5cefa2541ada4574c75e.jpg)
now take note that these inline fans only produce the CFM stated on box if its a straight vent. the flex vent restrict air flow. that was not enough for me because its a 1000w. so i bought a $3 fan and did this
![fan4.jpg](/data/attachments/83/83644-98328630b36dd5beee1762fe9750c1d4.jpg)
now in the summer i will replace the fan with a vent connected straight to the ac duct 1' away. then i found this really cool fan that has a thermostat on it.
![fan3.jpg](/data/attachments/83/83643-2d803db94577c231296bda0c1dcfa40b.jpg)
i placed it in the wall at floor level. (i built the wall so it was easy) and then i added these fans
![auxfan1.jpg](/data/attachments/83/83646-5448014fd511bb2702ab12ce1d960112.jpg)
this is probably the first thing i would do i move the ballast out side of the room.
hope this helps. i spent way to much time killing plants to figure this out and not share it with someone. also if your room is smaller then you can do it on a smaller scale. they have a 4" inline fan was like $12. watch out which hood you buy. pay attention cause some of them dont come with the glass, which IMHO is a rip off.