I've included a couple of items related to this forum

February 18, 2010



The Agricultural Research Service, USDA Aquaculture National Program focus is to help develop and ensure an abundant, safe, and affordable supply of seafood products within a healthy, competitive, and sustainable aquaculture sector.

On behalf of Jeff Silverstein, National Program Leader for the Aquaculture National Program, we have enclosed brief summaries of scientific research conducted in the areas of genetics, animal performance, nutrient requirements, improving health, and production systems and products that was completed over the last fiscal year. It is our goal to provide to you current information that can be used to support all areas of the Aquaculture industry.

Membrane biological reactor system shown to enhance performance of recirculating aquaculture systems. Recirculating aquaculture systems reduce water use by filtering and removing fish wastes and then re-using the water. Efficient removal of the wastes to maximize recovery of water, heat, and salt in the water is a major engineering challenge. Scientists at the Conservation Fund, Freshwater [COLOR="Red"]Institute working on an ARS project evaluated treatment of a high strength aquaculture wastewater using a pilot-plant membrane biological reactor to determine overall treatment performance, especially the removal of nutrients and metals. Researchers found that the treatment process removed more than 99.9 percent of the solids and most of the heavy metals, more than 99.8 percent of the total phosphorus, and 97 percent of the total nitrogen, while recovering 93 percent of the wastewater discharge. This research identifies better waste management technologies and practices that can be implemented to improve waste capture and disposal while allowing reclamation of water, heat, and salts.

Moving bed biofilters developed for low-cost energy-efficient production of marine fish. The low energy, water, and capital cost requirements of a “moving bed biofilter” make it an ideal component for the removal of toxic ammonia and nitrite from recirculating aquaculture systems. However, operational protocols and design criteria for optimal performance are lacking. In a series of collaborative studies by researchers from the ARS Sustainable Marine Aquaculture project and Harbor Branch Oceanographic Institute of Florida Atlantic University in Fort Pierce, Florida, scientists established operational protocols and design criteria, including optimal airflow, media flow, and media type, for moving media bed biofiltration technology. These protocols will reduce capital and operational costs for farmers utilizing recirculating aquaculture systems for the production of marine fish in underutilized inland rural sectors.