Ventilation for Grow Box question

[NorthernBoy]

Hey folks, first time poster long time lurker.

I got the ok from the wife lady for a grow box, first time growing and so far search has answered all my questions except this one...

I have a 48''x36''x77'' (lxwxh) cabinet I have built from my left over lumber pile, I will be adding a 600watt LED, with maybe 4 auto's going at a time. Now I was planning on a 4'' inline exhaust but the person who was liquidating there equipment could only find there 6'' fan, so the price was right but the fan was overkill so here I am with as 6'' exhaust fan at 490 CFM for that space.

Now the question is, with that 490cfm exhaust fan should I use a 70cfm bathroom fan for intake or that kind of CFM should I just be going a bunch of passive intakes?

Thanks for any help, you guys are some of the most helpful people I have ever seen. I have read thousands of posts and have had so many questions answered!

NorthernBoy

 

[Obi Wan]

I would go with 1 passive 4" intake.

 

[NorthernBoy]

Thanks for the reply, what do you think about multiple ports maybe 2 at 2"? Or is it more complex than that?

Thanks Obi Wan!

 

[Obi Wan]

I've run dual passive. I thought I'd like the ability to spread out the fresh air.

I found it better for climate control to run a single intake diagonal from the exhaust and use a circulating fan (which should already be in the room) to distribute the fresh air.

/Obi