Carbon filter inside or outside?

Just set up a new cab and I was wondering if it makes a difference wether the filter get the air drawn through or pushed through? It's a diy carbon filter made out of a 6"x6"x6" cardboard box with carbon pads and activated carbon between the pads. Latley ive been smelling the plants a little bit (I think I need to rebuild the filter) but I'm only in second week flowering and the holidays are approaching and I need it to be stealth!

I have room inside the box and I'm considering buying a "legit" carbon filter.

The exhaust is powere by a fan from a pc power supply I am unsure of the cfm.

Pull air through the filter. I've heard of others having success pushing through the filters but I cannot comment on that as I have never done it. I believe the manufacturers design them for air to flow from the outside in and not the other way around. My 2 cents.

Yeah If I were using a manufactured filter it would have the air pulling through. But mine is diy so is there any performance loss with it being pushed through? It's not shaped like a cylinder it's carbon pad walls within the box the filled with carbon inbeteeen the pads.

The filter is made to have air pulled through it not pushed.... Is on all the manufacturer specs. If u run out of room consider an air ballast box ( duct from grow to ballast incert filter inside then ur fan to exhaust.
U pull air through to allow adequate contact with carbon.... As to filter all smell not just most...not to mention is easier to hide the filter.

Will draw a diagram on air ballast if wanted ( is really simple)

If you made your own then you might just need to experiment and find out through trial and error what will work best.

I didn't buy one. I know what the air flow direction needs to be on a manufactured one. I'll just have to mess with my diy one and see what works best. I was just asking if it works better with a positive pressure I the fan pushing through a DIY filter or being pulled through a DIY filter.

Pull... U want a negative pressure so unfiltered air doesn't get forced through

daemon kronic said:

Pull... U want a negative pressure so unfiltered air doesn't get forced through

Click to expand...

Hm now I want to start over and build one that gets pulled through..... I may have leaks and that's why I smell it

Possible... The reason bought systems do it that way is to slow the air down ( soaking time) in the carbon... Ive tried both it does work better pulling but either way... U want no leaks.... Ive had much success doing a 4 tube filter ( use 4 tubes that fit inside eachother with holes inner most being 2" longer then rest, seal one end dump in carbon to all chambers cap other end attach fan)