FISH FARM TECHNOLOGY .I-BRACKISH WATER FISH CULTURE BASED ON "AQUAFEED"

Abstract

A method has been evolved to enhance the production of natural feed in brackishwater fish farms by providing substrates for biogrowth ('aquafeed' production) which is a biomass complex consisting of sedentary and associated organisms of plant and
animal species. The seasonal fluctuations of the aquafeed production over different substrates ranged as: 787-1830 gjcoconut leaf (6 m2)/45 days, 16.0-072.9 gjglass panel
(2 x 10 x 10 cm2)/30 days, 52-230 g/nylon mat (2 x 25 x 25 cm2) /30 days and 18.6-123.1 gjwooden block (6 x 10 x 10 cm2)/30 days. The average dry weight composition of the
major components of aquafeed obtained in the present study was sand-silt-clay 40%, protein 22%, carbohydrate (water soluble) 1.8% and fat 3.35~;,; (water content 85). Mugil cephalus of I .85 em reared in a 0.01 ha. pond and. fed on aquafeed attained a size of 23 em length and 146.73 g weight during one year. Survival rate was 54~;,; at a density
of 1 0000/ha. Salinity and temperature of the pond during the culture period ranged between 1.4 and 32.8% 0 and 28.1 and 36.5 oc respectively.