Intake fan

I would suggest as low as possible unless you have major heat issues. With a tent that small, just opening daily should be enough air intake 🌱👍

I leave the door pathway open and temps can reach 29c sometimes more in flower. I have a 200w LED. Decided to go for the 5inch as its only a quid more

2x2x4 = 60x60x120 In M thats .6x.6x1.2= 0.432m3 volume in your tent, considering your flow is 105m3/h that fan is more than enough to freshen it up. But as the boys said earlier it depends on your running temps. You also need to establish efficiency of your exhaust, if you have a CF with an exhaust thats a lower rated m3/h is your tent going to inflate like a balloon? :p

Either one will be fine but the 4 inch will manage jus fine. For that setup you only need to move 25m3/hr. Good luck and happy growing

Depending on how big a light but a 4 inch should do it. Heat build up is what I am referring. If it is like a 100 or 150 watt light a 4 inch should be enough

A 4 inch is enough for a 2’x2’