One side is totaly opened about 12x56cm (HxL) hole is on it, I tought the air can come in there, maybe I will put a PC fan there to suck more air in. This hole is absolutly down, above the basement. Maybe I can get the air out (with a tube) in this hole as well as get it in?
Not an option to make more hole on the cabinet, because this place is temporary for my plant. I want a little bigger growing cabinet....
Nice carbon filter, I want to make a similar one, just not sure how