I posted this in another place, but looks like there is more traffic here. \t\t\t\t \t\t\t\t \t\t\t\t \t\t\t\t\tVentilation. \t\t\t\t \t\t\t\t \t\t\t\t\t\t \t\t\t\t\t\t\t \t\t\t\t\t\t\t \t\t\t\t\t\t \t\t\t\t\t\t \t\t\t\t\t\t\t \t\t\t\t\t\t \t\t\t\t \t\t\t\t\t \t\t\t\t\t\t \t\t\t\t\t\t\tThis is the formula I have found in numerous places to calculate what size fan one will need. Example on left. My tent on right. LxWxH / 5 min 10'x10'x10' / 5 Min --------2' x 2' x 6' / 5 min = = 1000 ft^3 / 5 Min ---------24 ft^3 / 5 min = = 200 ft^3 / Min ------------4.8 ft^3 / 1 min = 200 CFM = --------------4.8 cfm So I will need 4.8 CFM doubled since I will be going through a carbon filter. Why do I need a inline fan that is way way way more powerful than the formula suggests? Am I missing something? Please help!! \t\t\t\t\t\t