Feed the Future Innovation Lab for Collaborative Research on Aquaculture & Fisheries

Effect of salinity on carrying capacity of a recirculation system for Nile tilapia, Oreochromis niloticus L.; production was assessed. Survival, growth and feed conversion ratio of adult Nile tilapia fed 30% crude protein diet for 88 days were measured at three different salinity levels (8, 15 and 25 g L⁻¹) and two stocking densities (20 and 40 m⁻³) in three independent recirculating systems. Highest survival (98%) and a linear growth in net biomass (P < 0.01) was observed in both densities at 8 g L⁻¹ and in 20m⁻³ treatment at 15 g L⁻¹. Highest net biomass growth was observed in the 40 m⁻³ stocking density treatment at 8 g L⁻¹ salinity level (P < 0.05). Overall biomass growth was significantly affected by salinity indicating a decrease in Nile tilapia carrying capacity with increased salinity. About 11,000 kg ha⁻¹ crop⁻¹ of Nile tilapia can be obtained in recirculating systems at 8 g L⁻¹ salinity, significantly higher than the net production at 15 g L⁻¹ (5,200 kg ha⁻¹ crop⁻¹) and 22 g L⁻¹ (4,425 kg ha⁻¹ crop⁻¹).

NOP 06-A13 (English)