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to stimulate the growth of algae. "It is generally considered to be the most essential single element in pond fertilization, and the first nutrient to become a limiting factor for plant growth (Piper, et al., 1986)". A total of 4.54 Kg of phosphate and 80.5 Kg of alfalfa pellets were added to pond #3 between 13 May and 29 June (Table 5.). Zooplankton was first noticed 5 June, 23 days after initial pond fertilization. It is not known whether any zooplankton was positively identified. On 10 June, 1500 razorback sucker fry, 4-5 days old, were added to pond #3. After 41 days, on 21 July, a sample of 27 fish was removed from the pond, and compared to a total of 321 fish (originally 600) used in feed trials. The feed trial fish were fed one of five different commercial starting diets, and confined to compartmentalized tanks in densities of 40 fish per compartment.. Both groups of fish were weighed and measured. The pond fish ranged in size from 40-55 mm TL and weighed a total of 23.48 g (0.87 g/fish). The feed trial • fish ranged in size from 13-27 mm TL and weighed a total of 13.21 g (0.04 g/fish). The difference in sizes and weights are probably due to the following reasons: 1) differences in the size of tank compartments (8"x6"x611) verses the pond (1/10 acre), 2) differences in fish densities between tank compartments and the pond, 3) differences in water temperatures between the tanks and the pond, 4) differences in dissolved oxygen levels of the tanks verses the pond, 5) the amount of food available to the fish in the tanks verses those in the pond. The fish in the tanks were fed a total of 0.01 g of diet, per compartment, per day. Feedings took place five to eight times a day. The fish in the pond had an unlimited food supply, 24 hours a day. In addition to the plankton available, other possible food sources, as the fish grew larger, may have included algae, aquatic plants, aquatic insect larvae and adults, aquatic