<p>This study evaluated the effects of biofloc technology (BFT) on male and female red tilapia (<i>Oreochromis</i> spp.) broodstock over a long-term rearing period, focusing on the pre-spawning and spawning phases. A total of 1000 mixed-sex acclimated fingerlings (36.88 ± 3.44&#xa0;g) to 18 parts per thousand salinity over 15&#xa0;days were assigned to either BFT or clear water control tanks. During the pre-spawning phase, BFT enhanced water quality, improved growth and feed efficiency, and significantly promoted reproductive performance and metabolic regulation in broodstock. During the spawning phase, broodstock were distributed into four treatments: (1) control (C–C), reared in clear water during pre-spawning and spawning, respectively; (2) BF-BF, reared in BFT during both phases; (3) C-BF, reared in clear water pre-spawning and BFT during spawning; and (4) BF-C, reared in BFT pre-spawning and clear water during spawning. Strategic BFT application significantly reduced time to first spawning and increased fecundity, egg quality, hatchability, and total fry production. Water quality remained superior, with lower total ammonia–nitrogen, NO₂-N, and NH₃, and higher NO₃-N and phytoplankton activity. BFT enhanced nutrient assimilation and reduced pathogenic bacteria, though prolonged exposure impaired physiological balance, reproduction, and hormonal regulation. To maximize benefits while minimizing risks, a phased BFT strategy is recommended. Specifically, BFT should be applied during the pre-spawning phase to enhance broodstock conditioning, reproductive development, and immune function, followed by a transition to clear water during spawning to prevent physiological stress and hormonal imbalances. This approach ensures optimal reproductive outcomes while maintaining long-term broodstock health. Future research should focus on refining BFT application based on species, size, gender, and specific nutritional requirements to further optimize sustainable aquaculture production.</p>