Look at John Galt's "cold upflow settling" WVO filtration set-up. I use my own version of it. My only modification would be the addition of a large diameter drain valve at the bottom of the first settling barrel. The better (although significantly more expensive) way is to filter using a centrifuge. IMHO.
http://www.frybrid.com/forum/attachment.php?attachmentid=2119&stc=1&d=1193006636