update: (as requested)
after the agravation of constantly changing the filter pads, I took the filter down long enough to redo the baffles. I almost trippled the filter pad section, and removed the small fish I was growing out in the sump.
as a result more sediment was trapped without clogging the filter pads and any particulates that pased through the pad settled on the bottom of the planted section. A small carpet of bright green algea started to cover the pad and some of the bottom of the planted section (no algea formed in the display). after over a week I'm still using the same pad and the algea is begining to disapear. the water is currently crystal clear and continues to read zero nitrates. The duckweed that entered the system on another plant and has, of course, thrived. I was woried that it would clog the pumps, but so far is not a problem. It does, however, do an excellent job cleaning the water.
pics to follow!