Growbox question

Hello,

So I am in the planning stage of building my growbox. As of now I plan on it being 31"x15"x30"(LxWxH). I plan on using 2x2's for framing and MDF or something for panels. I plan on using CFL's and to grow in coco coir. The question I have is regarding exhaust fan and the placement of a carbon filter/scrubber(still do not know the difference). I was thinking about using a bathroom fan(~88-117cfm). Do you guys think this will be a sufficient set-up? Also, where would I place the carbon filter-before the fan or after it? That is-should that fan pull through the filter or push the air out of it?

that fan will be more than enough for that area, as far as the placement of the filter, its up to you though I have heard that it is easier for it to pull the air through the filter than to push it through.

Thank you. That is what I meant as far as placement-which will be easier for the filter and result in a more efficient system overall? I have rough designs for both pull-through carbon filter and a push through one, but I just wanted to ask someone who has experience.