you should understand thast fans arnt used to just make the plants stems big enought to support the bud.(you could just tie the plants up ,and growth will concentrate soley on bud devolopement). fans are mainly used to keep co2 levels in a grow room a a resonable level not enought and the air goes stail and the plants cant breath.you need to be thinking about maintaining high co2 levels using vents,fans,extraction fans ,you name it. but the main thing to keep bud devolopement at it highest is to make sure co2 is in the room, then the plants can breath and grow much better.