To ensure a successful shrimp crop, pond preparation is an important technical step that should be paid attention to right from the start because well-prepared ponds can limit pathogens and create a favorable environment for shrimp growth.
At the beginning of the pond, when growing whiteleg shrimp, especially intensive farming, preparing the pond is the first technical step that needs to be done carefully. Because, not to mention the risk of spreading pathogens, it is also difficult for farmed shrimp to grow well if the captive environment is poor in nutrients or affected by toxic gases such as H2S, NH3 and NO2 (due to long-term accumulation). wastes from excess feed, shrimp manure and organic matter during farming). Therefore, to eliminate these harmful agents, people need to prepare the pond well according to the following notes.
Thoroughly clean and disinfect the pond bottom
1. Pond cleaning and disinfection
In order to eliminate all kinds of enemies (crabs, snails, insects, trash fish…) as well as destroy pathogens that may be present in the pond, it is necessary to drain the water, dredge the mud and conduct thorough cleaning and disinfection of the pond bottom. carefully follow these steps:
- Pond bottom pump to clean waste;
- Dig the soil with a depth of 5-10 cm, apply agricultural lime to kill bacteria and stabilize the pH of the pond bottom. Need to adjust the amount of lime to suit the pH of the soil;
| Soil pH | Amount of lime (ton/ha) |
| 4,5 – 5,0 | 1,5 – 2,5 |
| 5,1 – 6,0 | 1,0 – 1,5 |
| 6,1 – 6,5 | 0,5 – 1,0 |
Table 1. Amount of lime used by soil pH
- Supply water to the pond at about 1 meter and soak for 3 to 5 days;
- After that, wash all the water with quicklime and dry the bottom for at least 10 days before officially supplying water for stocking.
With old ponds, the time to dry the pond bottom should last from 1 to 2 months to completely interrupt the crop, kill pathogens, mineralize and restore the bottom environment. In addition, it is also necessary to repair and clean the pond banks, water supply and drainage systems, as well as fence nets, canvas, to limit leakage and avoid intermediate host species causing diseases from outside.
2. Prepare water supply to the pond
The water supplied to the pond should be thoroughly filtered and kept pure to minimize the density of pathogenic bacteria and ensure there is enough plankton in the water to make food for shrimp in the first month of culture. Especially with the model of intensive shrimp farming, it is necessary to build a settling pond to treat the water source before supplying it to the pond according to the following steps:
- When the tide level is highest, collect water into the pond through filter bags to limit garbage and enemies;
- Allow to stabilize for 3 to 7 days and then disinfect, disinfect in the morning (about 8 o’clock) or afternoon (about 4 o’clock) with TA-Superdine or Finishnano and other biocides approved for use in aquaculture. products such as Chlorine, Iodine, BKC…;
- Continuously fan water for 10 days to release germicidal residues;
- Stocking tilapia (size 50g/fish) into the settling pond at a density of 3-5 fish/m2 and maintained continuously throughout the process.
Next, the treated water is taken from the settling pond into the rearing pond through a filter bag to reach the water level from 1.4 to 1.5 meters and then proceed to color the pond water with TA-Gold according to the formula: 1kg TA- Gold +10kg rice bran + 5kg soybeans (ground) + 4kg molasses for 500 to 2,000m3 of water, incubated for 12-24 hours before splash into the pond.
Allow 5 to 7 days for the water color to reach standard, then check and adjust the environmental factors of the pond water so that it is within the appropriate threshold when stocking. To increase water quality, essential minerals can be added with TA-Mix 100 or probiotic products such as TA-Pondpro, but absolutely no inorganic fertilizers or chemicals are used during this period.
| Parameter | Unit | Allowable Value |
| Dissolved Oxygen (DO) | mg/l | ≥ 3,5 |
| pH | 7÷9, daily fluctuations do not exceed 0.5 | |
| Salinity | ‰ | 5÷35 |
| Alkalinity | mg/l | 60÷180 |
| Transparency | cm | 20÷50 |
| NH3 | mg/l | < 0,3 |
| H2S | mg/l | < 0,05 |
| Temperature | 0C | 18÷33 |
Table 2. Parameters of water quality supplied to the ponds
Once the water has been supplied to the pond and the color has been grown, the breed must be stocked within 15 to 30 days after that. To save time and costs, farmers can consider using ponds from the previous crop to continue growing the new crop if the amount of sludge at the bottom of the pond is small and the water quality is still good, but it is necessary to treat the water and the bottom with probiotics products with a dosage 2-3 times higher than normal before stocking.
Preparing the pond is an important technical step
In addition, farmers also need to pay attention to install a suitable venturis system to ensure the oxygen demand for farmed shrimp. And the pond preparation should also consider the different characteristics between different farming models such as semi-intensive, 1-stage intensive, 2-stage intensive or 3-stage intensive.
