Intensive Zero-Exchange Shrimp Production Systems - Incorporation of Filtration Technologies to Improve Survival and Growth

Cost effective application of superintensive, biosecure marine production systems in the U.S. will depend upon proactive management of culture-water quality. More efficient production practices and effective management of waste materials from the shrimp aquaculture industry can allow for higher productivity, improved growth and survival, and pave the way for eventual application away from coastal areas. These improved production strategies are key factors contributing to profitability and environmental sustainability. Development of cost-effective management strategies includes application of mechanical and biological filtration devices to remove solids and nitrogenous products from culture systems. Accumulation of these waste products can limit system productivity and negatively impact cultured animals, increasing the potential for stress, disease, and mortality. Technologies developed to remove solids and maintain concentrations of nitrogenous waste products within acceptable limits include different types of filters used alone or in combination with a variety of media types. All of these technologies have achieved varying degrees of success. While use of expandable granular biofilters is not new, improvements have been made in the design and composition of the filtration media. This, in conjunction with an appropriate backwash regimen, encourages attachment and growth of nitrifying bacteria to accomplish clarification and nitrification in a single unit. The purpose of this study was to evaluate the effects of biological and mechanical filtration on production and selected water-quality criteria in zero-exchange, biosecure, superintensive shrimp production systems.