Measurement of copper complexing capacity of grass prawn (Penaeus monodon) larviculture water. In：L.M. Chou et al. (ed.)

Abstract

Labile copper was measured by differential pulse anodic stripping voltammetty (DPASV) after a number of ionic copper spikes were allowed to equilibrate with the complexing material in the water sample. Different organic compounds were added daily into Penaeus monodon larviculture water, after which the water's copper complexing capacities were measured. Results showed that the treatment group with added EDTA-2Na (ethylenediamine telraacetic acid-2Na), EDTA-4Na and NTA (nitriotriacelic acid), with the cultivation time extended, had higher complexing capacities. The complexing capacities of the control group's culture water and treatment group with EDTA-2Na and NTA at Alysis II was over 40 ,ug/L. Using DPASV, the titration curve of copper and culture water complex showed that most of the complexes were strong stable nonlabile complexes. Therefore, dissoluble organic materials in the culture water could reduce the toxicity of heavy metals. With the exception of the treatment group with NTA, it can be concluded that higher complexing capacities of culture water can result in higher survival rates of P. monodon larvae.