Johnny5thesim
Well-Known Member
4 in filter is too small for a 4*4. Depending on how high of static pressure the fan is rated for it's likely too small as well.
A filter will reduce rated fan cfm output by 30-60%. I suggest at least a 6 in filter.
I use 8*24 filters for my 4*4 tents
I have a 4x4x6.5 tent. And I use a 4” 200 cfm on low for veg, and medium for flower. With carbon filter reduction and 2 bends in my ducting. I’m around 100cfm. Given my 104 cubic foot space. That means I’m getting a full exchange once per minute. And it keeps all my numbers in check. All the reading I’ve done seemed to suggest having a full exchange between 1-3 minutes is ideal.
I had a 6” fan and filter, and found it was way too strong even on low. I was struggling to keep my humidity up, cause the tent couldn’t retain any air fast enough. Going to a 4”, fixed that right up.
I can’t imagine an 8” inch being needed. We must have greatly different source environments!