Triplicate groups of red sea bream (29.0 ± 0.1 g) and olive flounder (24.5 ± 0.3 g) were fed one of the test diets for 12 and 9 weeks, respectively. In both experiments growth performance and feed utilization of the fish were significantly improved by dietary supplementation of KH compared to those of fish fed the control diet. Significantly higher digestibility of dietary protein was found in both species fed KH and TH diets, while higher dry matter digestibility was only found in flounder fed the KH and TH diets.