first grow box blueprints(rough)

drawing up plans for a grow box.let me know what you think, any advice? I will be using a 600w hps/mh digital ballast with 6'cooltube, 6' exhaust fan & carbon filter. the maximum size I can build45'x36'x79' I plan on 4 maybe 5 babies...... I have never seen this before but I thought it was a good idea,(FEEDBACK ON THIS IDEA WOULD BE NICE) in my design I have my passive intake inline with cool tube so cool air will always be flowing over the bulb. then into grow area, and the exhaust is prety standard

Your passive intake should be lower to let in cool air from down low.

since im using a cool tube could I have it hanging vertical so that the cool air will come out the bottom of the tube?

like this?

or is it better to hook the light up to exhaust and pull heat out with a normal passive?

Hook fan nd filter to tube pushing air through tube and sucking through filter passive intake at the lower portion