New grower need advice with cabinet

Hey everyone, My new cab is almost finished.. I think i have six or so seedlings in there but I have a couple questions about finishing my flower room. I have a 200-300 cfm fan I'm hoping to cooltube a 400 watt hps and have a carbon filter. Is this fan going to be strong enough?

Also I'm looking for ideas on how to vent my cab. i have 2 intakes in the veg side and 1 in the flower side so far and one light trap between the veg and flower side so far should i put more intakes in the flower side or the veg side so it vents the veg before the flower? any ideas welcome the space is really tight in the flower side so far with the big 6 inch ducting I'm worried its going to be hard to get a cooltube in there the dimensions are 19"Dx23"Wx53"H

Also is a 400 watt overkill in this space should I go with a 250 or will the 400 give me much better results?
Thanks in advance.

Well, I don't think a 400 is overkill, but you would probably get conflicting results from that type of question. If heat becomes a problem, you could always switch to a 250, but if I were in your shoes I would go with a 400.

As far as ventilation goes, the general rule is you need a minimum of 2x the passive intake size as you have in the exhaust. So if your exhaust fan runs off a 6" fan, then you need two 6" passive intake holes.

Other than that, your explanations have been very vague. What type of carbon filter are you using? A DIY? and if so which type? If it's a purchased one, what is the recomended CFM rating?

Also, there is a big difference between a 200 CFM fan and a 300 CFM fan. Either would probalby work fine, but when you give a description, there is a big difference between the two.

If your question is regarding heat, the general rule is to exchage the air in the cab 4x a min. So do the math and figure out what you need. Then over compensate a little bit for resistance, and the carbon scrubber, and that's what you would need. That would mean that unrestricted, 53 cfm would probably work well for you. Given the restrictions listed, the fan you have would probably work alright. Try it out and see how it runs, if it's too hot then add another intake hole, add a bigger fan, ect.