At the start of the experiment, 60 fish from each
treatment were anesthetized (100 mg l1, benzocaine)
and individual weight (g) was measured. These fish
were then randomly separated into three 19-l recirculating
tanks to give 20 fish per experimental tank. Ten
fish were killed with an overdose of benzocaine (400
mg l1) and frozen in liquid nitrogen for whole-body
chemical analysis. Water quality was monitored three
times week1 and water changes (~50%, with preheated
water) were performed as necessary to keep
water quality within the limits for barramundi (Tucker
et al., 2002). Dissolved oxygen was maintained at
N80% saturation with constant aeration in all temperature
treatments. Temperature was recorded twice
daily with a mercury thermometer.