in one row with one end more exposed to people passing by and occasional
daylight than the other. The four treatment combinations comprised two fish
weight classes (small and big) and two DO levels (low and high) which were
arranged in a 2×2 factorial: small fish–low DO (SL), small fish–high DO (SH),
big fish–low DO (BL) and big fish–high DO (BH). The small and big fish were
those obtained on 6 June 2006 and 7 April 2006 (see 2.1), with average weights
(±SE) at the end of the acclimation period of 20.00±0.33 and 140.87±1.80 g,
respectively. Dissolved oxygen concentrations below 3.5 mg L−1 were considered
low and above 5.0 mg L−1 were considered high