With that much CFM you definitely won't need any intake fans, lol. That tent will be sucking itself inward with all of the negative pressure.
4 fans total? or 2 fans total?
FYI Intake should be approx 2x what the exhaust is.
Intake should be twice the exhaust? So for 3000CFM hot air exhaust, i need 6000CFM intake? Wouldn't that create positive pressure? I thought negative would be better?
I calculate based on total inches/volume. Yes intake should be twice the volume as the exhaust for proper negative pressure. Same thing weed growers do to prevent odor/smells, keeps the air flowing in one direction only through a filter that gets rid of the smell. They use this same system.
You can buy flange kits up to 12" in duct size and customize/add them to your tent.