Water quality in aquaculture-Impact and management: A review

Water quality determines to a great extent the success or failure of a fish cultural operation Water is an inevitable medium for aqua farming, hence its quality has assumed a key role in aquaculture operations owing to its various interacting effects on the productivity of cultured animals. Effective management is of great significance in determining the success of aquaculture operation. This is particularly true for tropical ponds where deterioration of water quality is often encountered due to increasingly high rates of accumulation of organic matter in the pond bottom and its temperature induced decomposition in tropical ponds. As the pond ecosystems are basically cybernetic in nature, the stability of the system is achieved by the interplay of different subsystems of the ecosystem. In the present review, the role of physical-chemical factors such as temperature, dissolved gases, the CO2-CO2-HCO3 system, hardness, ammonium. nitrite, nitrate, phosphate and other parameters, which that act on the biological production has been discussed. Different management strategies such as mechanical, chemical and biological treatments required to maintain desired water quality in aquaculture ponds for improved fish production as well as to the ecosystem health have also been highlighted. Some models used for water quality management have been reviewed.