Gorilla tents are expensive. I have second guessed myself a bunch of times, but it is a well made tent.
You will be even less pleased when it shows up to your door in a box that is labeled gorilla grow tent. Not discreet at all.
CFM is cubic feet per minute, just like the rating of your exhaust fan. The person i was replying to obviously runs at a high negative pressure because the sides of his tent pull in.
Gorilla does offer a kit for that particular situation. I dont have the kit, and dont have a need for it