Need advice on ventilation

[PurpleHaze25]

Was wondering if anyone can tell me if the 2 small vents on the bottom of my cupboard count as an intake of fresh air, or will I need to buy a fan. Any advice appreciated thanks

 

[Vapeman420]

Looks like it could work as a passive intake, will you be exhausting with a fan? Are these up against anything or is the air free flowing around them? How big of a set up are you looking at?

-Vape

 

[PurpleHaze25]

It's about 2x3 foot carbon filter with extractor fan inside. I am going to switch to 12/12 in about a week or so. There has been no intake air flow except from these vents all through veg but was wondering if I am better having an mixed air flow fan as the intake for flower