Carbon Filters and Cfm

hi i would like to know if carbon filters slow down the speed of my fan by much, i got a 4 inch sunleaves windtunnel hooked up to a 6 inch 400 watt cool tube. it cools the light pretty well, but i dont wanna raise temps by much.
if so ill have to upgrade to a 6 inch windtunnel, if not ill save money.

not by much at all keep it 72 82

It will slow down your fan some, I don't think it will be enough to make a difference.