I actually have 2 running but I'm cautious to run the majority of the rest of mine primarily because it is the beginning of spring time here and I haven't found a viable solution to combat the massive pollen in the air right now. I understand that I'll obviously still make money if I continue to mine daily if BTC goes back up, its just I'd rather see where things go with the market before I put some time on the newer miners that I have.
How high is your electric rate? I'm at 9.6 cents/kw and I'm still making money. Can you not put in some Merv 3 filters to deal with the pollen without adding too much backpressure?
Maybe outdated but still some good overview.
https://www.cnbc.com/2018/02/15/the-cheapest-and-most-expensive-countries-to-mine-bitcoin.htmlAnytime you want to move in where I live let me know

or go to Venezuela

And for the other thing I would suggest to buy another 5k rpm fan for the intake and box with filter. But since I think you have more than one you should check out solutions for bigger fan for whole storage and some filtering.