[Question]Active vs Forced intake first grow box

[ChiefKief]

Hi guys,
So this is my first post here i want to say hi first.

• I am building grow box , it will be around 2,5x2,5x6 and i will have 400w hps light. Since hid lights create a lot of heat good ventilation is needed. i will try to get reflector with tube to cool the light but if i dont i still need to vent the room.
  
  
• So i want to know which is better passive air intake where i simply cut holes 2 times bigger than exhaust fan or just buy intake fan and go with forced intake .
  
• Also another question i have,since the dark periods need to be pitch black ,do i cover the fans with something at dark period or there is a way to build the grow box without need to cover the fans so the light doesnt come in. I will also use carbon filter at the exhaust but how about light in intake no matter if it is active or forced?

Thank you guys,
I wish you high yields and perfect temperature in your grow room

 

[ChiefKief]

EDIT: Sorry for my mistake, what i meant was passive vs forced air intake
Sorry guys

 

[amanda88]

Passive is the best ...take a look down in diy, theres a stikky on ventilation ....world famous one!

 

[ChiefKief]

Why passive is better?

 

[amanda88]

cause it sucks vapors from all over the place, like a shot gun in reverse, as a power assist will be dominate vacuum from one direction, you need all directions ..good luck