In the last days of June, Khanh Hoa province experienced severe heat, around noon the outside temperature reached 40 degrees Celsius, which is very unfavorable for white-leg shrimp breeding.
According to our records, in shrimp farming areas in soil ponds in communities such as Ninh Ich, Ninh Loc, Ninh Phu… (Ninh Hoa city) stocking must be stopped after harvest at present. However, when we arrived at Mr. Le Minh Chinh’s family’s tarpaulin-covered shrimp farm in Ninh Phu Township, things were different: the ponds were still stocked normally and the aeration fan for oxygen production was running continuously.
The shrimp farming area in Chinh is still operational despite the hot weather. Picture: Kim So
Mr Chinh said there are two reasons for farmers to stop shrimp farming at this time: in addition to unfavorable hot weather, investment costs such as feed, seeds and electricity bills have increased, while prices have risen. Commercial shrimp are at a low ebb, so it’s difficult to make a profit from farming.
Why is Chinh still stocking shrimp even at this point? He said it was thanks to him to farm shrimp using semi-biofloc technology, which combines three stages to fight disease, prevent pollution and reduce shrimp farming costs.
According to Mr. Chinh, semi-biofloc technology is no longer new. However, this technology brings many advantages in shrimp farming to clean and stabilize the environment through microalgae. Biofloc consists of heterotrophic bacteria, algae and humus that help purify water, provide a rich source of nutritious food for culture subjects and inhibit the growth of pathogenic microorganisms. Therefore, farmed shrimp grow quickly, fight diseases and ensure food safety.
“Currently, due to diseases of which EHP (microspores) is the most serious outbreak, traditional shrimp farming is at high risk, and farmers’ breeding methods are difficult to control. “When I switched to shrimp farming with 3-step combination technology, it helped me control all pathogens from seed storage to harvest,” shared Chinh.
Also according to Mr. Chinh, the three-stage shrimp farming helps reduce feed and electricity costs and fight pathogens from the moment of occupation. If there is a risk, it can be canceled early to avoid serious damage.
Mr. Chinh’s three-tier shrimp farming model in Ninh Phu Township, Ninh Hoa City (Khanh Hoa). Picture: Kim So
Mr. Chinh’s shrimp farming model is implemented with the following steps: Stage 1, shrimp are raised in a tank of more than 100m², the density is 25-50,000 seeds, the incubation period is about 30 days. At this point, the shrimp reach a size of 1,000 – 1,200 shrimp/kg and enter phase 2.
In stage 2, all rearing shrimp are transferred to outdoor ponds using semi-biofloc technology. The second phase of cultivation lasts about 25 days, when the shrimp reach a size of 200-250 shrimp/kg, the density is 500 shrimp/m2, and then goes to the third phase.
In stage 3, the stocking density is reduced by half, ie the stocking density is 250 to 300 fish/m2. By rearing for about 90 days, the shrimp reach an average size of 50 shrimp/kg.
Chinh believes that with the above farming method in the first stage, the farmer will reduce the food cost by about a third compared to the traditional farming method, and the electricity bill is only about VND 500,000 due to the use of a small capacity aerator. in the children’s room.
In Phase 2, it will also help farmers reduce feed and electricity costs by about half compared to traditional farming. In phase 3, farmers only have to invest in electricity and feed according to the needs of the shrimp stock.
“With such rearing, the feed coefficient (FCR) reaches around 0.8 – 0.9, the maximum is 1.0. As a result, farmers will reduce the cost of 1kg of farmed shrimp by about VND 20,000 compared to the traditional farming method,” shared Mr. Chinh.
Thanks to the semi-biofloc shrimp farming technology combined with three stages, Mr. Chinh has saved input costs and increased profit. Picture: Kim So
It is known that the production cost of 1 kg of farmed shrimp with a size of 100 shrimp/kg in the central region is about VND 85,000. If farming is not risky, people can reap a small profit. While Mr. Chinh’s shrimp farming model helps solve the problem of saving on feed costs and electricity bills, these are the two main factors that cause farmed shrimp production costs to increase.
Accordingly, at a stocking density of 300 shrimp/m2, Mr. Chinh stocked shrimp for 60 days to reach the size of 100 shrimp/m2, the investment cost is about VND 50,000/kg. At a selling price of VND 80,000/kg (100 pieces/kg), he made a profit of VND 30,000/kg of shrimp after deducting the fees.
To apply this model, all its ponds are lined with canvas, combined with an automatic siphon system, an aeration system, an automatic feeding machine and a generator. In addition to the pond system, Mr. Chinh also invests in microbial culture zones, using a mixture of probiotics incubated with molasses to create bioflakes in barrels that are regularly added to ponds.
It is known that from 2014 to the present, Mr. Chinh has successfully applied the semi-biofloc shrimp farming technology, while adopting the 3-phase method (or 3-phase shrimp farming), which is suitable for the reality of each culture.