This study aimed to evaluate the productive and economic performance of four stocking densities of P. brachypomus “paco” fingerlings in floating cages in Yurimaguas, Loreto. A completely randomized experimental design (CRD) was applied, establishing four treatments with stocking densities of 6, 9, 12, and 15 fingerlings/m³, with three replicates each. A population of 126 fry was used, distributed across twelve experimental units, over a period of 120 days. The results showed that the lowest stocking density (6 fingerlings/m³) yielded the best productive performance indicators, with greater growth (LG = 15.9 ± 0.3 cm, WG = 223.9 ± 27.4 g, SGR = 3.11 ± 0.04 %·day─1) and higher feed efficiency (FCR = 1.91 ± 0.03) compared to higher densities (9, 12, and 15 fingerlings/m³). In economic terms, this treatment also showed the lowest production cost (CPKg = S/ 3.33 ± 0.05), the be...