2 tent ventilation

Well after an odd set up, trying to make a 2x2 tent work in a 8x10 room I decided to just buy a 4x4 tent and vent them both out the house. I went with a 6" Hurricane Inline fan, 435CFM. I used as much ridged pipe as possible. I vented it out the basement wall to the atmosphere. Reduced to 4"...