Air flow

Hey Ghost, nice grow you got going on there, congrats. Personally wouldn't bother with a carbon filter unless you are worried about legality, smell is generally contained if you are venting outside. Big side note though if you do use a carbon filter you should at least double the CFM rating of the exhaust fan. Exhaust - up high (Humidity/Heat rises) Buy a 15w inline fan and have it suck in the air outside the tent about 1inch from the floor, c02 is very heavy compared to o2 and will gather at the lowest point in the house. You will certainly still need to keep some air circulation within the tent and prevent dead spots ,a small upward-facing fan spreading around the co2 as it comes in. Oxygen makes up 21% of the air we breathe Carbon Dioxide makes up 0.04% of the air plant's breathe Can never have enough circulation, you want the entire tent just happily "breathing" Good luck pal!