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Detailed technical instructions for brackish water shrimp farming

Brackish water shrimp farming techniques include a series of methods and processes to create an ideal living environment for shrimp in brackish water conditions. Below are the basic techniques to follow when raising brackish water shrimp:

Prepare the aquarium

Prepare shrimp ponds

To prepare lakes and shrimp ponds well, please follow the instructions below.

Renovating settling ponds and farming ponds

• Step 1: Drain the water in the pond and settling pond and remove harmful species in the pond from the previous farming season such as shrimp, snails, crabs, insects, and trash fish. Carry out dredging of pond bottom mud, repairing pond banks and water supply and drainage pipes. Level the sloping pond bottom towards the drain. Pond banks must be thoroughly compacted or lined with tarpaulin to prevent landslides and water leakage. Next is a mesh fence around the pond to prevent disease-causing intermediate hosts such as crabs, crabs, snakes, etc. from entering the pond.
• Step 2: Spread lime powder at a dosage of 20 – 30 kg/1,000m2 if soil pH > 4, and if soil pH ≤4, the dosage is 30 – 40 kg/1000m2.
• Step 3: Harrow the pond bottom thoroughly so that the lime soaks into the bottom, thereby destroying all living organisms and detoxifying heavy metals, H2S gas as well as neutralizing the pH of the pond soil. With a pond lined with canvas bottom, you only need to clean and disinfect it.
• Step 4: Dry the pond bottom for about 5-7 days. For ponds that cannot be dried, pump out all the water, then use a machine to rake the waste to the end of the pond, then pump the waste into the waste pond, then apply lime at the same dosage as step 2.

Note: After each farming season, the bottom of the pond settles and the farming pond must dry for about 1 – 2 months to interrupt the crop, then recover for the next crop.

Treat water, take water into the pond

• Step 1: Get water into the settling pond by passing it through a thick cloth filter bag to remove trash, larvae, and other trash creatures, then let it settle for 3-4 days.
• Step 2: Turn on the water fan continuously for 2 – 3 days to stimulate the eggs of shrimp, crabs, snails, etc. to fully hatch into larvae.
• Step 3: Use 30 ppm Chlorine to kill impurities and bacteria in the water supply in the settling pond in the morning at 8:00 a.m. or in the afternoon at 4:00 p.m.
• Step 4: Turn on the water fan continuously for 10 days to decompose all excess chlorine. Use reagents to check whether there is residual chlorine or not.
• Step 5: Pump water from the settling pond to the farming pond through many layers of thick cloth filter bags until the water level in the pond reaches 1.3 – 1.5 m, then let it settle for 2 days.

Note: Do not remove impurities in the pond and do not take water into the settling pond when:

• The water outside the canal/ditch has a lot of mucus, foam, and silt.
• The water source is in an epidemic area.
• The water source has a phenomenon of glowing in the evening.

Causes pond water color

Causes pond water color

The purpose of this work is to help microorganisms develop and stabilize the water environment to create a favorable living environment for shrimp. To cause water color, after 2 days of supplying water to the pond, do the following:

Method 1: Use composted bran

Composted bran will include rice bran, soybean meal, and fish meal mixed in a ratio of 2:2:1. This mixture will then be cooked and incubated for 2 – 3 days.

• At 7 – 8 am, bring Dolomite black lime or agricultural lime into the pond at a dosage of 100 – 150 kg/1000m3.
• At 10 – 12 noon, fertilize bran with a dosage of 3 – 4 kg/1000m3.

Repeat the above 2 steps continuously for 3 – 5 days until the clarity of the water in the pond reaches 30 – 40 cm.

Method 2: Use a mixture of molasses, rice bran, and soybean powder at a ratio of 3:1:3, incubate for 12 hours

• At 9 – 10 am, fertilize the composted mixture at a dose of 2 – 3 kg/1,000m3 of pond water, spray continuously for 3 days.
• When the water color in the pond turns yellow or light brown or bean green, the seeds can be stocked.

For ponds where it is difficult to cause water color or the water color is not durable, you should add mineral ingredients and silicon to keep the water color in the pond more durable.

In addition, you can also use microbial products to cause water color according to the instructions of a reputable manufacturer.

Note:

• Does not cause water color with inorganic fertilizers.
• Once the water has been collected, do not remove impurities in the pond.
• Check and adjust pond water environmental factors to ensure it is within the appropriate threshold before stocking.

Arrange the water fan system

Arrange the water fan system

The arrangement of the fan system and the running time of the fan must ensure adequate oxygen supply for shrimp, especially in the evening, night and early morning. Because these are the times when the amount of oxygen in the pond reaches its highest or lowest level during the day. On hot days or prolonged rain, it is necessary to increase fan running time or arrange an additional fan system in the shrimp square.

Location of water impeller

The fan is placed 1.5 m from the shore with the distance between the two fans being 60 – 80 cm, staggered. Depending on the shape of the pond, the water impeller will be arranged so that it creates the best flow and at the same time provides enough oxygen for the shrimp.

Number of water fans

For black tiger shrimp farming

Pond area	Density of 15 – 20 fish	Density of 20 – 25 fish	Rotation speed
2000m2	20 – 25 wings	25 – 30 wings	100 – 120 rpm
5000m2	50 – 60 wings	60 – 80 wings	100 – 120 rpm

For white leg shrimp farming

The oxygen demand of white leg shrimp is very large, so the fan system can be a water fan system with plastic propellers or a combination of plastic propellers with porcupine quill propellers or other propellers. The rotation speed of the plastic impeller should be greater than 120 rpm.

Pond area	Density	Number of fan blades (10 blades/array)	Number of porcupine quill fans
2000 – 3000m2	30 – 60 fish/m2	4 sets	1
	60 – 100 fish/m2	4 sets	2
4000 – 5000m2	30 – 60 fish/m2	6 sets	2
	60 – 100 fish/m2	6 sets	3 – 4

Select and release seeds

Choose breed

Choose healthy, disease-free shrimp seeds

Shrimp seed should be purchased from reputable establishments with negative test certificates for harmful pathogens. For shrimp seed size, black tiger shrimp will be P15 – P20, while white leg shrimp will be at least P12.

Check the health of shrimp seed by shocking, specifically as follows:

• Salinity shock: Take 40 – 50 shrimp seeds and put them in a glass cup containing 300 ml of water taken from the seed transport bag. Then suddenly lower the salinity to 15‰ and monitor the shrimp for 30 minutes. If the survival rate is 100%, it is satisfactory.
• Shock with formalin: Drop 40 – 50 shrimp seeds into a bowl or glass cup containing formalin solution with a concentration of 100 ppm, then monitor for 30 minutes. If the survival rate reaches 100%, it meets the requirements.

Stocking

– Stocking density

• Black tiger shrimp: Intensive farming is 15 – 20 shrimp/m2, and semi-intensive farming is 8 – 14 shrimp/m2.
• Whiteleg shrimp: For newly converted households, the density is 30 – 60 shrimp/m2, and for experienced households, the density is 60 – 80 shrimp/m2.

– How to release shrimp seeds

• Release in the early morning or late afternoon to avoid shock to the shrimp.
• Before stocking, you need to turn on the water fan for 8 – 12 hours to ensure the dissolved oxygen concentration in the pond is greater than 4 mg/l.
• To balance the water temperature between the seed bag and the pond, float the seed bag on the lake surface for a few minutes before slowly filling the bag with water. Next, hold the bottom of the bag and slowly turn it upside down to let the shrimp follow the water flow to the pond.

Shrimp care and management

The amount of food for shrimp will follow the instructions and be adjusted to suit actual needs such as shrimp health, weather, molting cycle, etc. During the farming process, monitor the feeding net or fishing net. when the shrimp is 20 days old or older to make appropriate adjustments. Feed the shrimp 3 times a day with the following dosage:

Feed the shrimp with the appropriate amount of food

During the first month of rearing

During this period, shrimp are fed small-sized food.

On the 10th day after stocking, put a little food in the sieve, tray or bowl to help the shrimp get used to it. This method is also easy to check the amount of leftover food later. The feeding sieve is placed on a flat place, about 1.5 – 2m from the pond edge, about 12 – 15m behind the water impeller. Note: Do not place sieves in the corners of the pond, the distance will be 1,600 – 2,000m2 for 1 sift.

After 15 days, you can use additional vitamins and minerals according to the supplier’s instructions to improve shrimp health.

• Black tiger shrimp: On the first day, give 1.2 – 1.5 kg/100,000 seeds, then increase by 0.2 – 0.3 kg/100,000 seeds every 2 days.
• White leg shrimp: On the first day, give 2.8 – 3 kg/100,000 seeds. During the first 10 days, each day increases by 0.4 kg/100,000 breeds. From days 10 – 20 onwards, every day it increases by 0.5 kg/100,000 breeds.

From the 2nd month of rearing onwards

Based on monitoring the amount of leftover food on the feeding screen, the shrimp’s daily food amount needs to be adjusted appropriately. Depending on each stage of shrimp development, the type of food will be changed. When switching foods, you should mix the old and new foods and feed them for at least 3 days.

Some notes when raising brackish water shrimp for high productivity

To have a successful brackish water shrimp farming crop, please note the following issues:

• Regularly monitor the weather situation.
• 5-10 days before stocking shrimp seeds, monitor weather developments and stop stocking if the weather is not favorable.
• Shrimp should be nursed in 2-3 stages and use large breeds to stock commercial shrimp.
• Nursery of shrimp before commercial farming will help improve the quality of the seed, creating healthy shrimp that can survive well.
• Do not use banned chemicals or antibiotics during the farming process.
• Choose quality shrimp seeds that have been tested for pathogens from reputable seed supply centers.

Above are successful brackish water shrimp farming techniques that you can refer to. Hopefully the knowledge we have just provided will help you have a successful shrimp farming season.