At one time a lot of fish could be found naturally in riverine Bangladesh. Since the population was less then, fish from natural sources would meet our demand for animal meat. Over time, due to population growth, application of pesticides in agriculture, filling of reservoirs, construction of unplanned dams, urbanization, emission of toxic industrial wastes, etc., the natural habitat of fish has been destroyed and the abundance of fish from natural sources has decreased day by day. In this situation, we have become dependent on ponds to meet the demand for natural meat including increasing fish production. Fish provides about 80 percent of the animal protein in our diet.
Fish farming is a profitable investment. Fish farming is a technique or method of producing more fish in a pond or pond that is produced naturally or by adding proper management and necessary materials in a pond based on science. It is possible to improve the employment, poverty alleviation and socio-economic conditions of a large population through fish farming.
In general, the fish farming method of the pond can be divided into three parts.
- Fish farming in traditional way.
- Semi-intensive fish farming.
- Intensive fish farming.
Prerequisites for fish farming are pond selection and pond preparation
The fish farming process is very fruitful if the steps of pond selection and pond preparation are completed properly.
Pond selection: Here the focus is on the selection of ponds for carp mixed farming. These fish eat different foods from different levels of the pond. Therefore, to ensure maximum utilization of natural food produced at different levels and to maximize the utilization of a pond for maximum production, the issues taken into consideration while selecting a pond should be considered.
If the pond is near the locality or the house, it is easy to manage.
Generally, two-fiber, clay two-fiber soil ponds are good for fish farming.
Fish can be farmed in ponds of any size. However, ponds of 30 to 1 acre size are more suitable. The edge of the pond should be high so that it is not flooded.
It is better if the water depth is 1.5 to 2 meters.
Pond preparation
The edge of the pond needs to be repaired and the floor leveled to get the expected results.
The bushes on the banks of the pond need to be cleared. If there is any tree that creates shade, it should be cut down.
The amount of mud in the old pond is more. So more mud has to be removed.
No aquatic weeds, giant and unwanted fish can be kept in the pond.
It is better to dry the pond and remove the fish completely. This giant unwanted fish can be removed by applying Rotenon as 40 g / percent / ft of water. The amount of water should be mixed with rotenone powder to make kani. Then separate 1/3 part and make small balls with it. The rest should be diluted in more water. Then during the hot sun the thin part should be sprinkled all over the pond and the balls should be applied evenly in the pond.
Polythene should be tied around the nose and hands while applying Rotenon; Sprinkle in the air favorably. These precautions must be followed.
Lime application: Lime is one of the various materials used in fish farming.
Benefits of applying lime: purifies water; Eliminates diseases; Removes water turbidity; Releases nutrients from soil to water; Increases the production capacity of the pond; Helps in the formation of fish scales and spines; Removes water impurities; Eliminates toxic gases, acts as a buffer.
Dimensions and methods of lime application: Lime should be applied at the rate of 1 kg per cent. In this case, the face should be covered with lime in a tin bucket or drum, cement jar with a sack. Then pour water gently on the sack. After 3 to 4 hours add more water and dilute and sprinkle in all the ponds. This work has to be done during the sun.
Caution: Lime should not be soaked in plastic containers; Lime should be soaked in earthenware or tin buckets or drums; When applying lime, the nose and mouth should be tied with a towel; Lime should be sprinkled in favor of wind, children should be kept out of reach.
Fertilizer application: Fertilizer should be applied 5-6 days after lime application. The natural food of the pond is made by applying fertilizer. Which is a necessary natural food for carp fish ponds. These are different types of phytoplankton and zooplankton. Fertilizer application depends on the fertility of the pond. However, it is better to apply the prescribed amount of fertilizer while preparing the pond.
TSP and mustard oil should be soaked in water at least 12 hours before application to the pond. When applied in ponds, it should be mixed with sufficient amount of water and sprinkled in all ponds. Urea fertilizer should be mixed with water and sprinkled before application. Things must be done in the sun. The level of fertilizer application is given in Table-1.
Natural food test: Natural food will be ready within 3 to 5 days of application of fertilizer. If the color of the water is light green, brown green and reddish green, then it means that the food has been prepared. Natural food can be tested in water in 3 ways. Such as: Seki disk method, by hand.
Seki disc method: Seki disc is a tin white black disc. Whose diameter is 20 cm .. Red, green, white are hung by these three colored yarns.
214.272 SRY