Author
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Pfeiffer, Tim |
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WILLS, PAUL - HBOI-FAU |
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Submitted to: International Journal of Recirculating Aquaculture
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 8/24/2009 Publication Date: 6/1/2010 Citation: Pfeiffer, T.J., Wills, P.S. 2010. Low-head saltwater recirculating aquaculture systems utilized for juvenile red drum production. International Journal of Recirculating Aquaculture. 10:1-29. Interpretive Summary: Recirculating aquaculture systems recycle and reuse water with mechanical and biological treatment between each use; thus they require wastewater treatment and filtration techniques for continuous waste removal. Compared with pond culture or flow- through aquaculture, a recirculating system generally occupies very little area, requires less water than conventional aquaculture, and provides a controllable environment for the culture species. Designed to conserve both land and water resources, recirculating aquaculture systems can be located in areas not available or affordable to pond culture. However, the techniques used for continuous waste removal from the system are relatively expensive. The development of an efficient wastewater treatment system that takes in to account the species culture conditions necessitates testing of various mechanical and biological filtration methods and techniques. In an effort to maximize water and energy use and increase fish production per unit volume of water low-head propeller pumps and air lift technology were used for water and filter media movement. Locally available fiberglass shops were used to build the biofilters for the large scale recirculating system (12,000 gal). The low-head recirculating systems were able to successfully grow out red drum fingerlings from less than one –inch to over six inches at high system carrying capacities, 0.5 lbs/gallon, with limited daily water usage, < 2% system volume. The low-head systems were successful in maintaining acceptable water quality for optimum fish growth under intensive culture conditions in a brackish water (12-15 ppt) environment. The USDA/ ARS research effort in Fort Pierce, FL is directed towards inland aquaculture for low salinity species and will continue to evaluated alternative methods for reducing the costs and simplifying the treatment process for low salinity recirculating aquaculture systems. Technical Abstract: Recirculating aquaculture systems reuse water with mechanical and biological treatment between each use and thus require wastewater treatment techniques for continuous waste removal. However, the traditional techniques and equipment utilized in recirculating aquaculture systems are expensive. The development of efficient wastewater treatment techniques that takes in to account the species culture conditions necessitates evaluation of various mechanical and biological methods and techniques. In an effort to maximize water and energy use and increase fish production per unit volume of water low-head propeller pumps and air lift technology were used for water and filter media movement. Locally available fiberglass shops were used to build the biofilters for the large scale recirculating system (12,000 gal). Solids removal from these systems were conducting by purging of the in-tank sumps, and the use of swirl separators, filter pads, sand filters, submerged media filters, and rotary drum screen filters. The low-head recirculating systems were able to successfully grow out red drum fingerlings from less than one –inch to over six inches at high system carrying capacities, 0.5 lbs/gallon, with limited daily water usage, < 2% system volume and at a comparable cost to pond production. The low-head systems were successful in maintaining acceptable water quality for optimum fish growth under intensive culture conditions in a brackish water (12-15 ppt) environment. |
