PC grow case fan placement

Hey, i'm planning on starting to grow vegetables inside my pc case.
I currently have a pc case with the following fan setup.
2 x 120mm intake fan on the bottom front of the case.
1 x 120mm fan on the top back of the case.
1 x 140mm fan on the top of the case towards the back side.
they are placed as followed in the picture.

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If i was to make the fan on the top of the case the external fan and all the other 3 internal fans would it be a suffucient air circulating?
also, what filters do I need to put on which fan's when growing veggies?

Thanks.

help anyone?

#1 you can exhaust with the fans at the top and use no fans in the bottom "passive intake" and be good
#2 you can put pantyhose over the intake

how would you block light with the fans at the top though

i guess you would have to make some sort of cover for it to prevent light leak

im making a veg box out of a full tower case, it has 2x big fat fans at the top that i dont wanna waste they were expensive lol