Yeah bro your box if fine ,but always remember you may have a male or hermie .
And if you think your box is to small, LST them i got alot of tips for LST and also other threads on the site .18/6 all the way untill your flower. Also about your bulbs it doesnt matter but make sure for 18/6 you got the 6500k bulbs on and get some 2700k bulbs for flowering .As for smell dunno your gonna have to see between all 18 of my grows i havent had 1 plant but male's stink up the room.Just so happens if your stuff is super dank during flowering ,those Airwick plug in things work amazing and also the got CFL 's that get rid of the smell