I walk near harvest, it stinks in the room where the tent is

You did not say what type filter you are using? Is it a thin sheet style or a large canister? My filter works well if I run my fan at 4 or lower (1 is lowest, 10 highest). If I run it higher the carbon filter can't absorb fast enough to keep up with the airflow. To help I run a larger filter. So, I use a 6" filter with my 4" fan and it allows me to run the fan much higher and still absorb odors. Also, carbon filters do not last forever. With heavy use and high humidity they don't last as long and need more frequent replacement.