fan size???

[ferdew]

im doing a small grow in a 120cm x 60 x 180 tent and im trying to work out the smallest fan i can get away with.Im kind of tempted to get a 5inch rvk L with a controller, however i have a friend who has given me a 4 inch rvk and he says it will be fine if i just run on full.Obviously it will save me money but am I unestimating what i need???..thanks

[Quotientcatalysed]

im doing a small grow in a 120cm x 60 x 180 tent and im trying to work out the smallest fan i can get away with.Im kind of tempted to get a 5inch rvk L with a controller, however i have a friend who has given me a 4 inch rvk and he says it will be fine if i just run on full.Obviously it will save me money but am I unestimating what i need???..thanks

4' should be fine , I got 6 inch for 120x120x200