Cheers on the grow light, looks like a good one. That will keep that pesky stretch in check.

Not that I know the right way to do it but I  will tell you how I go about it.

Maybe elevate the filter to the highest position you can safely get it in your tent. This will evacuate the hottest air from the tent along with as much odor as possible. Is that a 4 inch duct and filter? And please tell me that is not a vivosun filter, you will want to go with the infinity something or other on Amazon that is the same price next time, I  did the same thing.

On fan efficiency it will depend on a few things: the cleanliness of the dust filter& carbon filter, also what kind of fan do you have?CFM?& style.

On life span: going into more humid days will only shorten the life of the filter.  The volume of air that passes through the filter itself,  amount of fan draw (CFM).

The more, the shorter the life, but better odor control while filter is new.