randomly assigned to each diet. 24 groups each of 25 fish weighing 13.45 ± 0.04 g fish−1 (mean ± S.D., n= 25).
The feeding trial lasted 12 weeks, during which the fish were fed to satiation thrice daily (09:00, 13:00 and 17:00 h), 7 days per week. At each feeding, an excess amount of feed was fed to fish and uneaten feed were collected 1 h after
feeding, dried at 70 °C and reweighed. Leaching of uneaten feed was estimated by placing weighed samples of each diet into a tank without fish for 1 h and then recovered, dried and reweighed. The average leaching value was used to correct
the amount of uneaten feed.