Preparatory work to propose water-only tests with the amphipod Hyalella azteca. Comparison with sediment toxicity tests

We show that, when performing water-only tests in semi-static conditions with the amphipod Hyalella azteca, it is necessary to use sieves prepared as described in this paper. Feeding condition 0.1 mg/individual/working day appeared to be relevant to ensure optimal growth and reproduction. Finally, it seems that sediments do not provide extra benefit compared to prepared sieves, provided there is sufficient cover and some bacterial development.