yes that is the correct way to do it. turn that 8 inch duct fan around take the ducting off the intake side of your light and suck the heat out. it will pull your tent tight so you will lose a bit of space when its ziped up. but just keep your plants away from the walls. also put a dimmer switch...
Ganga luva
man that looks bad. i had a problem similar to that and it could be a number of problems. check for mites. it doesnt look like there on your leaves to me but there so bad that they
could be and there just hidden from all the browning.
Second thing defanitley dont foiler feed to...
Train grow that looks to me like its from water and nutrients getting on the leaves. the look ok but i would only feed once a week and
and if they get dry between the feedings just water them a little. Also buy sunshine mix, pro mix, fox farm, black gold, or any dirt that is made organic and...