Long story short my Grow cabinet has a small pc fan low pulling fresh air in and than 2 more pc fans on top exhausting the air. Both fans are inside the cabinet mounted against holes cut into the back wall of the cabinet. In order to connect a carbon filter I ran some 4" round pipe with a 6" booster fan on the outside of the cabinet connecting to the exhaust hole. My question is should I disconnect the pc fans? My initial thought was they would provide extra cfm feeding the booster fan. But now I think they may actually be restricting the air flow. What would work best for this situation?