New science-based farming technique for black carp: 200,000 jin raised in 1.5 mu of water

   1.5 mu of water produces what used to take 100 mu

    Won't the fish die doing this? Now this is what you call the latest science-based farming!

    Especially the use of medication, which is only 1/286 of that in traditional farming methods

    Shen Tianxiang is 49 this year and has been farming fish in Luxi Village, Zhiqian Town, Jintan, for more than ten years, mainly raising common aquatic products such as black carp and crucian carp. Recently he drained his pond to rebuild it. “With traditional farming methods in the past, 100 mu of water could produce 200,000 jin of black carp. Now that this new pond engineering-based farming system has been built, this 1.5 mu of water can, by conservative estimate, produce that much.”

    The pond is divided into three parts, and the main rearing area has only 1.5 mu of water

    “This new farming system has a very long name, so just think of it as ‘flowing water farming.’” Talking about this new farming method, Shen Tianxiang told the reporter that he is currently the first person in Changzhou to try this brand-new farming method. This time he set aside 100 mu of water to test this new system, spending more than 300,000 yuan, bringing in multiple aeration pumps and carrying out a thorough overhaul of the pond.

    After the renovation was completed, the 100-mu pond was divided into three parts. On one side is a first-level water source purification area of more than 80 mu, on the other side is a second-level water source purification area of about 15 mu, and between the two water source purification areas another 1.5-mu area with 8 small ponds was partitioned off. This is the main rearing area, and each pond has an aeration discharge outlet installed beneath it.

    Shen Tianxiang explained that the principle of this new farming system is to use aeration equipment to release oxygen or use water pumps to accelerate the flow of water between the main rearing area and the purification areas, ensuring the water quality in the main rearing area. “The fish that used to be raised in 100 mu of water are now all raised in this 1.5 mu of water.”
Electricity costs are 3 times the past, but management and feed costs have dropped sharply

    “To raise in 1.5 mu of water the fish that used to take 100 mu, ensuring oxygen content is very important. The aeration pumps must run 24 hours a day, and that is no small expense.” As for the new farming method, in Shen Tianxiang's view, the biggest expense is electricity. “Someone in Suzhou has already successfully tested this new farming system. According to their statistics, the electricity cost is more than 3 times that of traditional farming methods.”

    Relative to the increased electricity costs, Shen Tianxiang says this new farming method saves much more in costs. Management and feeding are much more convenient than before, and waste from feed application has also been reduced. “Think about it: in the past the fish were scattered across 100 mu of water, and a large portion of the feed was wasted. Now the fish are all in this 1.5 mu of water, so how much feed loss can there still be?”
Better water quality, fewer fish illnesses, and much less medication used

    “The biggest features of this new farming system, besides reducing costs and increasing efficiency, are that it is more ecological and environmentally friendly, the fish are healthier, and the amount of medication used is also much less than before.” Feng Jun, deputy head of the Changzhou Aquatic Products Station, told the reporter that with past farming methods, fish feces and uneaten feed settled at the bottom of the water. Over time the water quality deteriorated, and the levels of nitrite, sulfide and other substances in the water increased. Fish then easily became sick, and farmers needed to apply large amounts of medication to ensure the fish survived.

    The new farming system, however, creates a circulating water flow that washes away the feces deposited at the bottom of the main rearing area. The flowing purified water can also ensure the water quality in the main rearing area. “The levels of nitrite, sulfide and so on in the main rearing area of the new system are very low. The fish are healthier, and if they do not get sick, no medication needs to be applied.” Feng Jun told the reporter that according to the farming data from the new system in Suzhou, the amount of medication applied is only 1/286 of that in traditional farming methods.
 
    Because this is the first year using the new method, 100,000 jin fewer black carp are being raised

    But for farmers, economic benefit comes first. “This year is the first year using the new method. I am rather conservative and only dare to raise 200,000 jin.” Shen Tianxiang explained that according to the system's standard, raising 300,000 jin of black carp in this 1.5-mu main rearing area would be no problem at all.

    In addition to the main rearing area, Shen Tianxiang's two water source purification areas have also been put to use. Shen Tianxiang told the reporter that in his first-level water source purification area of more than 80 mu, he will raise about 100,000 jin of black carp at low density, while in the second-level purification area of about 15 mu he will stock some freshwater shrimp and snails. “The 200,000 jin of black carp in the main rearing area plus the 100,000 jin of black carp raised at low density is already a 50% increase over the past. Add in the freshwater shrimp, snails, and the silver carp and bighead carp that purify the water source, and the increase in income is far more than 50%.” Shen Tianxiang roughly calculated that the profit on black carp is about more than 2 yuan per jin. With the same 100 mu of water, the new farming system can increase income by more than 300,000 yuan per year compared with traditional farming methods.