Effect of hardness and ammonia on survival during captive nursery rearing of fish seed in net cages in Srikakulam District, Andhra Pradesh

Quality fish seed availability in right time is the major constraint for the development of aquaculture in Srikakulam district of Andhra Pradesh. Captive nursery rearing of fish seed Indian Major Carps Catla (Catlacatla), Rohu (Labeorohita) and Mrigala (Cirrhinusmrigala) up to fry stage in net cages was studied to know the effect of water quality parameters especially hardness and ammonia concentration on survival at 20 locations by Krishi Vigyan Kendra, Srikakulam. Three to five day old spawn stage fish seed was released at the rate of 1, 50,000 numbers in each cage. It was observed that highest survival 38 per cent and lowest 25.33 per cent, where the hardness and ammonia concentrations were in suboptimal range. The average survival rate and net profits observed were 32.18±3.83 per cent and Rs.9331/-, respectively. Based on the above results it is recommended that, nursery rearing of fish seed is a remunerative, reduces losses during transportation and assures the quality fish seed in required quantity.