hello mates, i kinda agree with all of you, i think if its your first grow then start at the bottom cos no doubt ya gonna make some mistakes, tubes are great for clones and young plants but i dont realy think they pack enough punch to thicken the buds towards the finish, however you can grow with them, i personly would go with a 250 hps all the floors, walls, and ceilings i would cover in tin foil,this would not only reflect light around the plants but would protect the wooden cubard your using, a small osilating fan would cool and cerculated air,you would of course have to make an opening to allow fresh air in, and if smell was a prob then you should vent it up a chiminy all the best bro,