The purpose of this experiment is to the effect of various carbon sources in the biofloc system on growth performance, feed utilization, hematological indices and body biochemical composition, of red tilapia under varying stocking densities. A set of 300 red tilapia fingerlings in good health, weighing 2.44:2.55±0.19 g on average, were cultivated for 14 weeks at a density of 100 and 150 fish/m³ in fiberglass tanks (75 L). Eight treatments, representing four distinct carbon sources molasses, sugar, and rice bran as well as control (clear water) were used in the design of the experiment, with two stocking densities of 100 and 150 fish/m3. Three times a day, the fish were fed commercial feed with a protein content of 32%, up to 5% of their body weight. Growth, and feed utilization were all significantly impacted by the addition of carbon sources, according to the analysis of variance data. According to the data, molasses and rice bran produced the best growth performance, feed utilization and hematological indices for red tilapia at a stocking density of 100 fish/m³.