if we make a whole in the wall infront of this one, and a little higher with another fan blowing from INSIDE the box to OUTSIDE, what size should it be??

since the fan sucking in is 6", should the exhaust be like 8"?
thanks guys!
calichin9 Reviewed by calichin9 on . First Grow: White Dwarf :) Okay this is my first time trying to grow, i know things are gonna mess up and I am gonna learn but any advice and comments would be greatly appreciated! Okay I got 12 White Dwarf seeds that my cousin brought from Spain. Sent up the grow box to be 2 1/2ft x 2 1/2ft. The light is a 125watt HPS light 1 6" fan Mini air duct built into the wall Organic Soil (cannot find Guanno ANYWHERE here in CR) Lights are 16/8 and here are a few pics of the grow so far Ill keep uploading pics throught Rating: 5