Intake & Exhaust for cabinet

[kokoiv]

Hello friends,
Ive been wondering about ventilation in small cabinet areas. Im attempting my first grow and while reading through several literature ie. Growing Elite Marijuana by Ryan Riley ive come to a little question. Like in every tutorial how to set up your grow room its stated that youre supposed to have a intake - and an exhaust hole best combined with a fan on each. But then, taking a look at the pictures it looks like theres just the vent somewhat build close to the light for coolings. No hole, no extra fan for the intake / exhaust.

So my question while growing with CFL's in a 35"x 20"x 13" cabinet. Aiming for 2 - 3 plants scrog trained for the begining:
Do they actually mean having 2 fans for intake and exhaust while having a vent for extra ventilation.

Or is it possible to just have 2 fans inside without holes for intake and exhaust? It being enough refreshing air by opening the cabinet for watering etc

thanks in advance

 

[poina]

It's my belief that passive ventilation is always the best solution. A rule of thumb is passive ventilation requires 2 times the area of your extraction fan.
Whatever dimension you have to cut to fit your fan (which should be on top of your cab, as heat rises) you must cut 2 of the same size for your passive intake (on the bottom of your cab).

Properly sized ventilation is the first key to micro grow success. Don't scrimp and use computer fans. Panasonic whisper fans are silent, however quite large, S&P also good, fantech, to name a few. These fans will work well for vent/odor control and will allow for light upgrade to hps if you're going cfl route for now.