4x4x7 grow tent 6in intake fan question

Should I just get another for outtake, and if so what do I do with the one I have in the mean time? use it as intake?

Read that question and see if it even makes sense to you.....
Why would you need another for exhaust? All you really need is a carbon filter that goes to a fan that pulls air out of the tent. This will cause a negative pressure that will pull fresh air in, no need for an intake fan.

but its a grow tent and its all sealed, seems like I would need something to pull air in from the outside, or you saying the negative pressure will pull air in from the gaps and stuff?

No you need to open a couple of the dedicated flaps and maybe make a light trap or two. It is suggested that you have 2x as much area for passive intake as exhaust, so if you have a 6" exhaust open 2 6" vents for intake.

repped, thanks