Rod Middleton, Kentucky Department of Fish and Wildlife Resources, 120 Fish Hatchery Road, Morehead, KY 40351, and Brian C. Reeder, Dept. Of Biological and Environmental Sciences, Morehead State University, Morehead, KY 40351

Abstract. Some Ohio hatcheries have experienced increased fish yields and reduced anoxia in hatchery ponds fertilized with inorganic fertilizer, when compared to those fertilized with organic fertilizer. At Minor Clark Hatchery in Morehead, Kentucky, we fertilized three hatchery ponds (0.41 ha) using traditional hatchery methods, and three with inorganic nutrients. Organic fertilization included adding chopped hay, soybean meal, alfalfa meal, potash, and 9-18-9 fertilizer. Inorganic fertilization used 28-0-0 fertilizer and phosphoric acid. By monitoring weekly, inorganic fertilization kept pond N (ammonium and nitrate) concentrations at 600 ug L^-1 and SRP concentrations at 30 ugl^-1. Survival in organic ponds averaged 87% (382 kg fish ha^-1); in inorganic ponds we only had 37% survival (177 kg fish ha^-1). It may be that inorganic fertilization is ineffective in southern hatcheries; however, exceptionally cold spring weather may have affected our results.