Effects of Density and Water Quality on Red Tilapia (Oreochromis mossambicus × O. urolepis hornorum) in Pulsed-Flow Culture Systems
Titel:
Effects of Density and Water Quality on Red Tilapia (Oreochromis mossambicus × O. urolepis hornorum) in Pulsed-Flow Culture Systems
Auteur:
D'Silva, Accio Moura Maughan, O. Eugene
Verschenen in:
Journal of applied aquaculture
Paginering:
Jaargang 5 (1995) nr. 1 pagina's 69-76
Jaar:
1995-06-22
Inhoud:
A study was conducted in which different densities (l0,20,30,50, and 70 fish/m3)of red tilapia (Oreochromis mossambicus × 0. urolepis hornorum) were stocked into 25-m3 sections of irrigation ditches and the effects of a pulsed-flow aquaculture system on growth and water quality (dissolved oxygen and ammonia concentrations) were evaluated. Results indicated that densities of 10 and 20 fish/m3 had significantly higher (P < 0.05) individual weights than fish stocked at 30, 50, and 70 fish/m3. Water quality limited the density of fish that could be cultured in this type of pulsed-flow culture system. Ammonia concentrations were periodically high (4 mg/L), and dissolved oxygen levels were periodically low (2 mg/L). Results indicated that densities of 30, 50, and 70 fish/m3 had significantly higher (P < 0.05) ammonia concentrations and significantly lower (P < 0.05) dissolved oxygen concentrations than fish stocked at 10 and 20 fish/m3. Overall, the density of 20 fish/m3 showed the highest level of marketable production.