At 48, 96, 144 and 192 h after hatching, 10 fish were sampled in each tank 30 min after the distribution of brine shrimp nauplii. They were anaesthetised with 2-phenoxy-ethanol (0.4 mL L−1) and their total body length (TL, mm)was measured under the stereomicroscope with a micrometer (accuracy ranging from 0.05 to 0.1 mm, depending on fish size and magnification). The anaesthetised fish were killed
with a lethal solution of 2-phenoxy-ethanol (over 2 mL L−1) and preserved in 5% formalin. Thereafter their guts were dissected under the stereomicroscope and food intake was determined by counting the number of brine shrimp nauplii in the foregut (then stomach when differentiated).