I run a brewpub with a 7bbl system. I have a 20 inch filter housing that I've used on a few occasions, experimenting with a few different sizes of filter (1/2/5 micron). For the most part, though, I haven't really been filtering any of my beers. I have a few brands that I would like to polish a bit more, and now that I am canning some I'd like to put together a useful filtration system that expands on the 20 inch housing that I have. I'd like some input on what has worked for others, and maybe some insight into variables that I should take into consideration.

I am thinking of getting two more filter housings and running them is a series of decreasing micron ratings. Here's the setup that I have in mind:

10" @ 5 micron
20" @ 2 micron
20" @ 1 micron

Would it make more sense to stick with all 20" filters? I suppose that'd offer some extra flexibility. This will all be modular enough that I can put one or two off depending on the application. But with, say, a light american lager in mind for the highest degree of polish I'd be shooting for, what changes might you make? Bump that 2 up to 3? Drop the 1 to 0.5?

I have the advantage of having a large producer of filter media in my town: Global Filter. I've purchased directly from them for the cartridges that I've used in the past.

Thanks for your input.