This work was designed to advance environmentally sound aquaculture through the development of low-pollution feeds for the commercial production of Sciaenops ocellatus and Penaeus vannamei. The first approach sought to reduce waste production by enhancing digestion of feed ingredients. This research evaluated two feed supplements (a protease and an acidifying agent with pro-biotic properties) for their effect on apparent protein digestibility (APD) values for Sciaenops ocellatus and Penaeus vannamei. Although the responses were different, protein digestibility values were increase by 6.7 and 12.7% through the addition of an acidifying agent in fish feeds and the protease in shrimp feeds, respectively. The second approach was to optimize the lipid component of a previously developed nutrient dense diet, designed for Sciaenops ocellatus juveniles, and to further optimize nutrient retention and minimize the deposition of intraperitoneal fat. For this research varying levels of menhaden fish oil (MFO) and medium chain triglycerides(MCT) were evaluated as energy sources in a basal diet containing 44% protein and 5.7% lipid. The supplementation of an additional 3% MFO was required for maximum growth and feed utilization; however, higher levels did not effect growth or feed utilization but facilitated lipid deposition in the fish.