Explanation:

Availability of required quantity of seed of the desired species at the appropriate time is one of the prime factors that lead to success of aquaculture operation. Though remarkable success has been achieved over the years in spawning the carps, availability of seed of desired size still remains a constraint. The nursery rearing involve nurturing of 72-96 hours old spawn which have just begun to eat and continues for a period of 15-20 days, during which they grow to fry of about 25-30 mm. These fry are further reared in another pond for a period of 2-3 months to raise the fingerlings of about 100 mm in size.