That's was what I was thinking. I'm only in day two of flowering and don't want to learn anything the hard way this far into my grow. I havent started to run any fans other than the ocsillating fan. I will be adding a 6" inline booster fan for the 600 HPS light and a 4" inline booster fan to bring fresh air into the room. Do I need another fan to just take air out of the room for the high humidity?