Finfish Breeding and Hatchery Management

Unit 5 - Fish seed rearing techniques

5.1.2. Fertilization

• Fertilization is an important step in the preparation of nursery pond. The main purpose of manuring nursery pond is to stimulate the production of zooplankton, the most preferred natural food of carp spawn and fry.
• After liming (200-400 kg lime per ha, depending upon soil pH), nursery ponds are treated with either organic manures such as cow dung (10,000 kg/ha) or poultry manure (5,000 kg/ha) and a small quantity of inorganic fertilizers (NPK at 200-400 kg/ha).
• When mahua oil cake is used as a piscicide for eradicating unwanted animals the dosage of organic manure is halved.
• Whenever phytoplankton blooms appear they can be controlled by sprinkling liquid cow dung or by covering the surface of the pond with the duck weed, Lemna. The duckweeds are removed after the blooms have been controlled.
  

Application of cow dung as a manure in a carp nursery pond