Craig S. Tucker

Pumping Performance of a Modified Commercial Paddlewheel Aerator for Split-Pond Aquaculture Systems

AbstractThe split-pond aquaculture system consists of a small fish holding basin that is connected to a waste treatment lagoon by two conduits. Split ponds require large water volumes circulated between the two basins (10,000–20,000 gal/min for 5–10-acre ponds) to remove fish waste and provide oxygenated water to the fish. Farmers producing ictalurid catfish in the USA have rapidly adopted this new technology to improve production efficiency. The original split-pond design used large, slow-rotating paddlewheels to circulate water; in this study, we evaluated paddlewheel aerators as pumps for split ponds. Pumping performance was evaluated at rotational speeds of 25–66 rotations/min and paddle submergence depths of 4.0, 6.8, and 9.5 in. Water flow rates ranged from 8,240 to 25,069 gal/min. Flows increased with increasing rotational speed and paddle submergence depth. Power input varied directly with flow rate and ranged from 1.08 to 8.28 hp. Water discharge per unit power input (i.e., pumping efficiency) ra...

Reducing Size Variation in Hybrid Catfish Culture through Graded Partial Harvest

AbstractHybrid catfish (female Channel Catfish Ictalurus punctatus × male Blue Catfish I. furcatus) have quickly become a major contributor to ictalurid catfish aquaculture in the United States. Hybrid catfish have unique production characteristics compared with Channel Catfish, and rapid adoption of the hybrid by fish farmers has outpaced research on appropriate management practices. This study was conducted to determine the effect of midsummer partial harvest of faster-growing fish on production characteristics in ponds with hybrid catfish in single-batch culture. Twelve 1.0-acre ponds were stocked with 10,000 year-class 1 hybrid catfish (~0.12 lb/fish) in mid-March 2015. In August 2015, six random ponds were partially harvested to remove fish larger than ~1.25 lb using an in-pond, flexible-panel, grading sock. In October 2015, all ponds were completely harvested. Partial harvest of faster-growing fish removed ~26% of fish from ponds in August. Removal of faster-growing fish resulted in 0.9% of the tota...

Comparison of Phytoplankton Communities in Catfish Split-Pond Aquaculture Systems with Conventional Ponds

AbstractThere has been a growing interest and use of variations of partitioned aquaculture systems (PAS) in recent years by the southeastern U.S. catfish farming industry. Split-pond systems, one type of PAS, are designed to better manage fish waste byproducts (e.g., ammonia) and dissolved oxygen levels than the conventional earthen ponds that have been used by farmers for many decades. Recent studies have focused on design, water flow rates, and other management areas of catfish split-ponds, but so far there has not been a focused examination of phytoplankton community composition and biomass in these split-ponds. In the current study, pond water samples were collected from split-ponds at a research facility in western Mississippi and at a commercial fish farm in western Alabama approximately every 3 weeks during the fish grow-out period (May to November). Water samples were analyzed for chlorophyll a concentration (phytoplankton biomass) of several major phytoplankton divisions and for types of phytopla...