sorry, i just saw your posting, and i had a few questions... how are your biowheels holding up? i ditched mine on my emperor400, as well as the filters. could not get my nitrates down, they were off the chart. i had a few of the powersweep ph's as well, but they crapped out on me. i eventually rebuilt them, taking out the rotating feature and filling in the space left by the assembly with silicon. 8O how are yours holding out?
