related to the improved feed palatability of the diet but cautioned that improved palatability may not continue if the fish became adapted to ‘‘less palatable’’ all-plant diets. In the present study, feed efficiency was affected by water temperature, fish meal level, and their interaction(Table 2). At 178C, feed efficiency was significantly higher in fish fed the fish meal diets than fish fed the all-plant-protein diet. However, the improved feed efficiency in fish fed fish meal diets at 178C did not result in significant increase in weight gain. The reason for this is not clear. Although there were significant differences in the weight gain of fish fed various levels of fish meal at 218C and 278C, no significant differences in feed efficiency were noted. This could related to the improved feed palatability of the diet but cautioned that improved palatability may not continue if the fish became adapted to ‘‘less palatable’’ all-plant diets.