Before initiation of the experiment, 20 fish were stocked in each tank and acclimated to the experimental conditions for 2 weeks and fed diet 2 once daily to apparent satiation at 0900 hours. After acclimation, fish in each temperature group were pooled and graded into a uniform size, and 10 fish were restocked in each tank.
Initial fish weight averaged 9.6 6 0.1 g/fish. Four tanks were assigned to each diet 3 water temperature combination. All fish were fed once daily as much as they would eat within 60 min to ensure that fish were satiated. The total feed consumption was recorded daily. Fish were counted and weighed collectively (bytank) every 3 weeks. At the end of week 9, feed consumption and weight gain per fish, feed efficiency
([ftotal final fish weight – total initial fish weightg weight of mortalities removed]/total feed consumption),and survival were determined.