I always wondered how odor control was in a cardboard setup. I run a passive air system with a big ass centrifugal fan pulling the cab's warm air thru my light hood over the bulb and out the cab I am using. I have holes cut for the fresh air and my fan is big enough to pull in the fresh and pull out the heat and thru a scrubber, but I can see how cardboard could be tricky to get just right without putting so much work in that it would have been better to become a carpenter and make a wood box. I will be tuned in cause your possibilities are endless and I am sure I will learn to think differently on small cab setups.:thumbsup: