Heavy Metals in Seawater of a Fish Hatchery System

This study was conducted to determine Cd, Cr, Cu, Fe and Pb concentrations in the seawater of a fish hatchery and to compare the values obtained with several Marine Fish Culture Standards (MFCS). Six sampling places across the hatchery system were selected for monitoring over a 10-month period and analyzed with Atomic Absorption Spectrometry (AAS). Results showed that the heavy metal concentrations were lower than the MFCS, except for Cu. The concentration of Cu was high in the broodfish recirculating tanks (St. 4) where it measured 19.35 ± 7.76 ug/L and in the effluent (St. 6), where it was 10.57 ± 11.48 ug/L. Copper sulfate added into the broodfish recirculating tanks as algicide treatment appears to be the main reason for this high Cu concentration. In the water intake (St. 1) and the settling tank (St. 2) the concentrations of Cd, Cr, Fe and Pb exhibited a greater range of fluctuation than in other stations. This might be due to the discharge of rivers which open in Sepanggar Bay, sediment-seawater interaction, current, tides and other dynamic processes. The study concluded that the concentrations of heavy metal in the hatchery of Borneo Marine Research Institute can be considered to be within the permissible level for aquaculture activity. However, the operating procedure at the broodfish recirculating tanks may be further improved for still better water quality and fish rearing conditions.


This paper was presented in the Annual Seminar on Marine Science and Aquaculture - Marine Ecosystems and Aquaculture Practices in Changing Climate, 11 - 13 March 2009