The study aimed to evaluate the impact of different carbon sources on biofloc generation of Nile tilapia, Oreochromis niloticus and common carp, Cyprinus carpio. 360   healthfully Nile tilapia and common carp were subject to an experiment for the current research work. The Nile tilapia had a starting body weight of 6.5±0.4g, while the common carp had a starting body weight of 6.9±0.1g. The samples were divided into six equal groups, with the initial three groups designated for the Nile tilapia and the remaining groups for the common carp. Each group was duplicated three times with 20 fish in each replication. Four diets were adjusted for the experiment. The first and fourth groups, serving as control groups, were given a baseline control diet containing 25% crude protein (CP). Groups two, three, five, and six were given a basic diet with 25% CP, along with additional molas and starch for carbohydrate supplies.The trial extended for 60 days. Both the Nile tilapia and common carp exhibited  the highest feed conversion ratio and  a superior weight gain when provided with starch and molasses compared to the control group. There was no notable change in water temperature across the groups. The biofloc groups had higher oxygen levels compared to the control group. Ammonia levels decreased in all treated groups in comparison with the control groups. The Nile tilapia and the common carp experienced an improvement in both growth performance and water quality in a biofloc system utilizing different carbon sources.