Method of culture of fresh water prawn or Galda prawn : About 70% 0fthe exported prawns are Galda prawn. They are cultured in inland, rivers, canals, ditches, haor etc of the country. Ponds with viscous soft clay soil with humus soil are suitable for Galda culture. The Galda prawns are widely cultured in the soft soiled ponds of Khulna, Jessore, Patuakhali, Noakhali, Chittagong, Comilla, Mymensingh and Dhaka. The ponds have to be suitably prepared for prawn culture.
· There should be two sluice gates in the culture ponds of Galda for the entrance and exit of water.
· The banks of the ponds should be elevated and the depth of the pond should be medium. If the bank is grassy, then it would not be distorted.
· The predatory fishes are to be removed before the release of the fries in the pond. The bottom of the pond should be cleaned, and lime and cowdung manure would have to be applied. This helps in increasing the fertility of the pond and planktons grow enormously. As a result the prawns grow faster.
· For a better production, only the desired varieties of prawn fries should be released in the pond.
· To earn the desired prawn fries several hatcheries or egg development tank have been established in different places of our country. Mother Galda prawn with naturally fertilized eggs, are to be set free in the hatchery, where regular anddefinite quantity of food, is to be supplied. The mother prawns lay 7,000 to 30,0000 eggs at a time. Within 16-24 days the eggs hatch to small nauplius larva. The larvae are to be supplied artemia (one type of Arthropoda) and other necessary foods regularly. The nauplius larva gradually grows to an adult passing through several stages.
Besides this, larvae are also collected from natural source for pond culture. In Bangladesh naturally hatched prawn fries are collected from the rivers of Kowkhali, Noakhali, Noapara, Kalughat, Halda, Dakatia, Rampal, Dumuria, Posur etc.