The overall objective of the polyculture experiments was to develop an economically viable, intensive polyculture system. Shrimp were to be the primary crop, with bivalves and fish used to maintain suitable water quality while minimizing energy requirements for water flushing and emergency aeration. Attainment of this objective required the establishment of bivalve and fish stocking densities that would optimize their cropping rates on phytoplankton and zooplankton such that phytoplankton are maintained in log-phase growth. Secondarily, the bivalves and fish may provide an additional crop for market.