Optimum velocity profile of water inside a portable FRP carp hatchery for rohu (Labeo rohita Hamilton) seed production

In this paper an effort has been made to optimize velocity profile of water inside a portable FRP carp hatchery for Rohu (Labeo rohita Hamilton) Seed Production at Central Institute of Freshwater Aquaculture (CIFA). Velocity Distribution at Different Depths and Locations in the Hatching Pool for a Discharge of 0.25 L/s during Hatching Operations were quantified. The variation in surface velocity is in the range of 54 to 74 mm/s from the outer wall towards the screen. But with depth the velocity increases upto the middle and then reduces towards the bottom. Velocity at surface of the tank is higher than bottom of the tank in the same vertical column. Minimum water requirements for breeding and hatching operations were quantified to be 6.946 and 82 cubic meter respectively. The minimum water requirement for the whole process was quantified to be around 90 cubic meters for a production of 1 Million spawn. Water qualities like- temperature, dissolved oxygen (DO), NH₄⁺, pH, and NO₃⁻ were recorded during the process. All the water quality parameters were well within the favorable range. Optimum velocity inside this FRP hatchery was also quantified. The velocity distribution inside the FRP hatchery followed a conovolumetric pattern, with minimum at the top and bottom and maximum at the middle section.