Home Made Air Filter

Ok, so I finally got around to building my air cleaner today......I had intended to build it into the rafters to save space, but with the low ceiling (7 foot basement) and the lack of a clean run of rafters (wiring, plumbing, hvac, lighting, ect. has made me build a free standing one. So i've built it to use 20x20 furnace filters. It uses a 370 cfm fan from a kitchen chimney hood. which I intend to duct over into the next room to dump the clean air. The thought behind this plan is to increase the air pressure in the other room, decrease it in my shop, thereby creating an ever so minor breeze back into the shop.

Anyhow.....my current stage is deciding on the number and type of filters. I'm trying to decide between 2 and 3 filters. Heres what I plan on using for sure.....

Stage 1
http://www.menards.com/main/heating-cooling/air-filters/pleated-filter-20x20x2/p-1719790-c-6856.htm

Stage 2
http://www.menards.com/main/heating...-filter-cartridge-merv-11/p-113730-c-6856.htm


Should I use this one for a 3rd and final stage?

http://www.menards.com/main/heating...-filtrete-ultimate-20x20/p-1781892-c-6856.htm



My concern is that a 3rd stage will reduce air flow......however the air would be cleaner.


Thoughts?