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10-11.50C, and dissolved oxygen levels ranged between 4.8-7.6 ppm (Appendix C). The fish were fed a total of 20,638 grams of commercial trout diet, and 31 mortalities were recorded. A total of 40 mortalities were recorded for both tanks #1 and #2. This leaves 77 mortalities unaccounted for. Six of the nine mortalities recorded for tank #1, and most of the mortalities recorded for tank #2, appear to be due to an infestation of Chilodonella species. The Chilodonella was positively identified by Don Toney (Steve Severson - personal communication). Chilodonella is a small, oval, colorless protozoan, 50-70 micrometers long, which may be found in large numbers on the skin, fins, and gills of fish (Piper et al., 1986). Symptoms of heavily infested fish are listlessness, non-active feeding, and flashing. The symptoms of fish held in tanks #1 and #2 were weak swimming and flashing. Treatment involved bathing the fish in a solution of 25 ppm formalin and .25 ppm malachite green for 4-6 hours (chilodon DPT treatment). On 31 January, four fish from the tanks were sent to the Federal Disease Control Center at Fort Morgan, Colorado. These fish were diagnosed as having no infectious diseases, and 2 out of the 4 fish were saturated with gas (Letter 1). Figure 6 shows a comparison of the differences in sizes (TL) between pond #2 fish and tank fish. Statistical analysis performed on these fish revealed that both groups appear to be normally distributed. An independent t-test (Table 4) showed that there is a significant difference in mean size (TL) between the two groups of fish (p = .05, df = infinity, t-critical = 1.96 (2- tailed), t-calculated = 3.58). At the 95% confidence interval, the mean difference in TL = 2.87 +/- 1.57. Also, an independent t-test (Table 5) showed that there is a significant difference in mean weight between the two groups of fish (p = .05, df = infinity, t-critical = 1.96 (2-tailed), t-