Chand Fish Seed Company Bandhaghat, Howrah, West Bengal

The larvae emerging from the fertilized eggs after hatching is called hatchling. It is characterized by the presence of yolk sac hanging below from where it draws its nutrition for 2–3 days. At this stage the mouth is not formed and hence it does not take food from outside.

Grass Carp are herbivorous fish which have been introduced to waterways around the world for aquatic control. The young fish will eat almost anything but as they get larger, they will eat more and more soft , which is why they are regularly used as a biological control. They won’t eat hard such as reeds and lilies. Given space, food and time they will grow pretty big but in small ponds they grow to the space and food available to them, which makes them ideal for control in small ponds.

As soon as the spawn assume the shape of the fish and grow to about 1–2 cm it is known as fry. At this stage they are primarily smaller size zooplankton feeder. It takes about 7 to 10 days for the spawn to grow up to fry stage.

As soon as the fry grow up to 10–15 cm size or roughly equal the size of a finger it is known as fingerling. Fingerling is the proper size for stocking in table fish production ponds. It takes about 30–60 days for the fry to grow up to fingerling size.

Method of rearing of spawn to fingerling stage in two steps is called double stage rearing.Initially the spawn is reared up to fry stage in nursery ponds. It takes about 7 to 12 days. Afterwards, they are transferred to relatively bigger size ponds known as rearing ponds where they are reared up to fingerling stage.

common carp are not native to our area; they introduced into Amrica from Asia as a food sorce.Unfortunately, carp hurt our native fish species by uprooting plants, disturbing the bottom, and eating fish egg.Beside fish egg, carp eat algae, other water plante, insects, earthworms, aquatic worms, snails, mussels, crayfish, and rotifers.They also eat old dead plant part ftrm the bottom.common carp swim along the bottom, suking up mud and food items. They spit out the stuff they don"t eat.carp are most active in early morning and evening.common carp spawn (breed) in weedy areas.

Catfish may have up to four barbels: nasal ,maxillary (on each side of mouth), and two pairs of chin barbels , although pairs of barbels may be absent, depending on the species. Because their barbels  are more important in detecting food, the eyes on catfish are generally small. Like other ostariophysans , they are characterized by the presence of a Weberian apparatus . Their well-developed weberian apparatus and reduced gas bladder allow for improved hearing as well as sound production.Catfish have no scale; their bodies are often naked. In some species ,the mucus-covered skin is used in cutaneous  respiration ,where the fish breathes though its skin . In some catfish, the skin is covered in bony plates called scutes ;some form of body armor appears in various ways within the order. In loricariods and in the Asian genus Sisor , the armor is primarily made up for one or more rows of free dermal plates. Similar plates are found in large specimens of lithodoras . These plates may be supported by vertebral processes , as in scoloplacids and   in Sisor, but the processes never fuse to the plates or form any external armor By contrast in the subfamily Doumeinane (family Amphiliidae) and in hoplomyzontines (Aspredinidae), the armor is formed by expanded vertebral processes that form plates. Finally, the lateral armor of doradids , Sisor, and hoplomyzontines consists of hypertrophied lateral line ossicles with dorsal and ventral lamina.