What can I use to prefilter the water and how can I rig it up? Ideally,
I'd like it down to 5 microns to save wear and tear on the UV.


If you're planning to get a standalone UV sterilizer, then your intake will be
a powerhead. That's what drives water through a standalone. You have to buy
it separately.

So the prefilter for the UV sterilizer will be the prefilter for the powerhead.
There are a variety of prefilters for powerheads on the market; check them out
in catalogs, online, etc.

I use a Penguin powerhead. It came with a foam prefilter, and it works fine.
I wouldn't worry about wear and tear on the UV sterilizer. Basically, it's
nothing but a hollow tube that the water passes through. Small particles in the
water won't cause any real wear and tear; there are no moving parts or
anything.


Leigh

http://www.fortunecity.com/lavender/halloween/881/