My 2 plants are growing in a 2x4x5. I NEVER had a problem with temp issues. my temps stay 75-80 with humidity (50-70). My plants grow great & I see progress everyday. maybe not the fastest progress but this is my first grow so I don't know how fast they are suppose to grow Anyways, my question is... is it necessary to have a exhaust fan? all I have is a incline 6" fan and I have the screen vents on my tent open for fresh air. I don't care for a carbon filter. smell is no problem for me when it comes to flowering stage.
You don't need an exhaust fan if the plants are getting plenty of fresh air, and smell is not an issue. It might be helpful to use an exhaust fan, because it will suck in fresh air as it exhausts. If you do this try not to let exhaust and intake mix, because the exhaust will have slightly less co2.
As its your first grow maybe not until they hit bud then you are gonna wish you installed one ...lol if you have done everything correct..fingers crossed inlet air is sucked passively from the room the tent is in that sucks out loose oder thru a say 4-6 inch vent a bathroom extract fan is a cheap alt. if you don't have this yet ..? then use a 6 inch deask top fan to remove C02 from around them leaves but only when lights are on why....weed is a C3 plant good luck
At least one inline fan is necessary for exhaust. I’ve always used passive intake. Fresh air will always come to replace the air being sucked out.