i was going to go passive exhaust w/ the carbon filter
and have a fan in the intake
easier for me to setup
Not saying it isn't possible, but it really isn't the "industry standard" around here.
Most people use the fan as exhaust, with a passive intake. Reason why people choose this, and not what you have in mind, is if you use an active exhaust, if you have a few cracks in the sides or whatever, air gets sucked in through these cracks, so no smell leaks. Your way, instead of no smell getting through all of those cracks, smells are actually PUSHED out those cracks. Plus, if you put the carbon scrubber on the passive exhaust, the air will usually chose the path of least resistance, meaning the air would actually PREFER to go out the small cracks, instead of the filter, creating even more smell. Save yourself the time, and the headache and go with a passive intake, active exhaust.
As far as light proofing goes, most people on here use caulk and weatherstripping. Read up on a few threads, it's in every one of them.
I personally don't like this stuff, because eventually it wears out, and it's kinda expensive in the long run. It would cost me probably $20 in weatherstripping to seal the door way, which would last about 3 years or so, probably less, then I would need to replace it. And that weather stripping stuff is not easy to remove.
I go to a fabric store, get a product called "Black Out". It's a white cloth material that is light proof, they use it to make curtains out of. It's about $5 a yard, so for $20 I can get about 4 yards of it, way more than I'll ever need. Then I cut a strip, and roll it up. I take this roll and place it on the doorway (or in whatever crack you have), staple it in place. Since it's cloth, it molds to the doorway, so everytime you close it, it seals the door. It's light proof, so no lightleaks, and it's actually air proof as well. (not 100% about this, but I can't seem to get air to pass through it, so ...). The stuff will last forever as well. Installed some about 5 years ago, still works amazing.