Each week, fish were sampled to estimate growth. Initial treatment biomass levels were reestablished at that time by removing fish from each system. Hand-feeding, six times per day, at a rate of 5% bw/day, commenced immediately after stocking. Fish were fed a 3.2 mm commercial floating catfish diet (Rangen, Buhl, ID), which we determined to have the composition presented in Table 1. Feed was refrigerated at 2°C until use. Fecal solids were partially removed on a weekly basis from each system. The solids were then dewatered and dried for proximate analyses.