The Effect of Stocking Density on Fish Growth and Survival in Intensive Cultivation Systems

Stocking density is one of the most critical management variables in intensive aquaculture, directly influencing fish growth, survival, feed efficiency, physiological health, and economic profitability. While higher densities may maximise space utilisation, they simultaneously impose cumulative stress through water quality deterioration, competition, and physiological disruption. This study examines the effects of stocking density on growth performance and survival of cultured fish through a descriptive quantitative analysis of 31 peer-reviewed publications (2021–2023). Quantitative descriptive statistics were computed for thematic distribution, annual publication frequency, and key performance indicators including specific growth rate (SGR), feed conversion ratio (FCR), survival rate, and physiological stress biomarkers. Results demonstrate that excessive stocking density reduces SGR by 8–42%, increases FCR by 10–35%, and decreases survival by 5–28% relative to optimal levels. Dissolved oxygen declines of 12–38% and total ammonia nitrogen increases of 25–80% were the primary water quality mechanisms mediating these effects. A non-linear optimal density range was identified across species: 1.8–14.6 kg/m³ for juveniles (0–28 g) and 14.6–38.4 kg/m³ for sub-adults (29–98 g). Biofloc technology mitigated 20–40% of water quality degradation at high densities but did not eliminate biological stress ceilings. This study concludes that medium stocking density consistently yields the best balance of individual growth, survival, and economic return across diverse species and production systems.