smoke24answered grow question 3 years ago ac infinity work well. I would also make sure your exhaust fan and connected duct work are air tight. Is your exhaust fan the right size for the tent you are using? If the tent is more than 3x3 you will need a 6 inch exhaust, 3x3 and under will be fine with a 4 inch. One final thing......you can run two carbon filters, one on the intake, and one on the exhaust, this allows for double the filtration. Hope this helps, happy growing.