Grass Carp Farming Helps Farmers Increase Income: Tiny Grass Carp Swim Out a Path to Prosperity

Over the past few days, workers at the Longyou Longhe Fishery Park have been releasing more than 100,000 grass carp into the newly built "raceways." The "raceways" where the fish exercise are 8 culture tanks, cast in concrete, located in the center of a 50-mu fish pond, each 22 m long, 5 m wide and 2 m deep. The culture tanks, arranged in a single row, have fish-blocking grates at both ends; the "water-pushing and aeration" device on the north side keeps the pond water on both sides circulating 24 hours a day, while the suction device on the south side constantly collects fish feces and leftover feed. The grass carp in the tanks vie with one another to swim against the current, constantly wagging their tails; on the splashing water surface, there is nothing but the dense, dark backs of the fish schools and the dazzling spray kicked up by their tails.

"This farming model was designed by Auburn University in the United States and introduced through the American Soybean Association; it is called in-pond circulating flowing water fish farming, also known as 'raceway fish farming,'" said Zhang Shuangqi, head of Longhe Fishery. Each tank is stocked with 25,000 grass carp, and two rounds can be raised in a year, producing 400,000 jin of grass carp annually, 4 times the output of the original 50-mu fish pond. "The fish schools are 'penned' in the tanks and kept moving, so they have beautiful lines, strong bodies, better quality and a higher price; the 8 'raceways' have an annual output value of more than 3 million yuan."

Small water bodies raise fish, large water bodies raise water. Zhang Shuangqi explained that pushing water and adding oxygen sets a pond of still water in motion. The fish feces and leftover feed produced during farming follow the circulating water flow into the suction channel, and about 80% can be recovered and made into organic fertilizer, while the remaining 20% is collected and used by the already-built pond bottom sewage discharge system. The whole process discharges no water to the outside. In addition, filter-feeding fish such as bighead carp and silver carp are raised in the fish pond, and plankton and aquatic plants further purify the water quality.

Yu Jin, head of the Fisheries Section of the Longyou County Water Conservancy Bureau, said that fish farming in clear water is friendly to the external environment but greatly reduces economic benefits. "Raceway fish farming" is scientific and environmentally friendly, not only efficiently purifying the water body of the fish pond itself, but also greatly increasing the fish farming density and quality, doubling the benefits and achieving a win-win outcome for ecological and economic benefits.

The novel fish farming model has also made more than 100 fish farmers in the Longhe Aquaculture Professional Cooperative eager to try it. Wang Zhiyin, a fish farmer in Baima Village, Mohuan Township, rented more than 40 mu of ponds to raise fish a few years ago, but lost so much money that he could not even pay the rent. After joining the cooperative, technicians taught him hand by hand techniques such as disease prevention and control, partial harvesting and restocking, and pond bottom sewage discharge. By putting adult fish on the market at staggered times, he earned nearly 200,000 yuan that same year, not only repairing his house and buying a car, but also adding a reselling business. At present, Wang Zhiyin's farming water area has expanded to more than 100 mu, driving more than ten village households to prosper together, and they are all very optimistic about the development prospects of "raceway fish farming."

It is understood that at present, Longyou County's fishery output and output value account for 1/3 and 1/2 of Quzhou City's respectively. Longhe Fishery's mature and efficient farming and sales model has a positive reference value for promoting fishery efficiency and increasing fishermen's income, and is also a good channel for precisely helping low-income farmer households. Zhou Xiaoping, director of the Longyou County Poverty Alleviation Office, said that in April, the poverty alleviation office will allocate special funds to be invested as shares for low-income farmer households in Longhe Fishery; each year, no less than 10% fixed dividends will be provided to subsidize low-income families.