Growth experiments
Acclimated PL were exposed to the different concentrations of copper and zinc, 17 singly or in mixture, in plastic trays containing 10 l of the experimental medium, for 35 days. Every 2 days, the experimental media were totally renewed. During the exposure period, PL were fed ad libitum with nauplii (first 15 days) or adults of Artemia sp. At the beginning of the experiment (N 543) and after 35 days of exposure (N 513–129; Table 1), PL were captured, measured (total length) and weighed (wet weight and dry weight). Experiments were performed in duplicate. Results were submitted to Kruskal- Wallis analysis followed by a posteriori test described in Conover (1980).