Abstract: In this study Daphnia magna enriched for three different time period (3, 6 and 9 h) and non-enriched Daphnia magna were fed to the whitefish fry (average weight 54.7±0.5 mg) during 14 days. A significant growth difference between fry fed with enriched and non-enriched Daphnia was observed (p<0.05), while survival rate did not significantly differ among the treatments (p<0.05). Furthermore, the highest pH stress resistance was found in those larvae fed with Daphnia enriched for 9 and 6 h (p<0.05). We observed that feeding of the whitefish larvae with HUFA-enriched Daphnia resulted in growth improvement compared to non-enriched Daphnia. Therefore, to achieve higher production, nutrition optimization of the whitefish larvae especially by using HUFA in daily foods and transferring it to fish body through live food is recommended for whitefish hatcheries. The result of this study proved that feeding the whitefish with live food containing high n-3 HUFA content increased larval resistance to pH stress.