Organisms that live in which zone often participate in nightly migrations?

I believe the "midnight zone" if that's what you're looking for?

Or the ocean twilight zone.

poor water quality affects most estuarine organisms, including commercially important fish and shellfish. the pollutants that have the greatest impact on the health of estuaries include toxic substances like chemicals and heavy metals, nutrient pollution (or eutrophication), and pathogens such as bacteria or viruses.

i think that is new experiments yield untrustworthy data and should be carefully considered, because you don't know what will happen with the experiments.