A few Questions about my Growbox

So here's my grow box I built last week. 4x4.6x8 (the inside still needs to be painted flat white)
I'm using 4ft 6 bulb t5 hos for vegging and a 600watt hps and the t5s wall mounted for flowering




1) Would a valuline 6in 435cfm be adequate to pull air throughout my light and carbon filter? Then push it through my window?
http://www.horticulturesource.com/c-a-p-custom-automated-products-centrifugal-fan-6-435-cfm-110w-1-amps-with-attached-2m-cord-jh150b-p4894/?osCsid=4a74f1abc3cd6c9e92e32fd8e04f408f

2) Or should I use a 12 in valuline with supposedly over 1000 cfm or an 8 in with 745 cfm to be on the safe side? Will reducers effect air flow? Which one of the 3 would you use? Pros/cons?

3) should I use booster fan or passive intake? Why? How big of a booster fan? How big of a passive intake hole?

4) Also is this fixture high output? It says HO in the title But not in the details
http://www.businesslights.com/tcp-elite-t5ho-lamp-4ft-multivolt-prs-high-bay-fixture-qship-p-2316.html

First off it so far everything looks great.

1. I just bought that fan today, for the price its hard to beat in my opinion...the cords a little short thats my only complaint.

2. If you want to go bigger you could always just buy a fan speed controller to tune it down, you can always turn down a big fan but you can't turn up a little fan . I personally am using one 6" fan to cool 2 1000w's (non-simultaneously). Reducers will always do exactly that, reduce airflow. I'd go for an 8 with a speed controller, not huge, quiet, power saving, and best of all adequate.

3. I like passive intake because there is zero odor, and plus you're drawing out so much air the negative pressure is going to equal itself out eventually. That brings in a good amount of fresh air without allowing odor to get out.

4. not familiar with florescents, maybe someone else can get this one for ya.

Good luck, and keep posting progress

30,000 lumens, it's HO.