Sea-based fish farming systems using net pens are hard on the environment and the fish. A closed cage can improve fish welfare, but fresh seawater must be continuously circulated through the cage. However, ocean waves can cause this circulating water to slosh inside the cage, creating violent motions and endangering the cage and the fish.
source https://phys.org/news/2021-03-sloshing-motions-sea-based-fish-farming.html
