https://teachbesttech.org/best-underwater-cameras/

Most of the underwater world is a pelagic (the surface waters of the sea) environment far from the coast. There are forms of life that stay there constantly and there are others that spend only a certain period of their life in this open water. Plankton, which consists of a multitude of drifting organisms that are not able to determine their position in the water, is transported by the current. Best Underwater Cameras In reality these organisms have a limited ability to move which they use to ascend or descend, creating what is known as "vertical migration". This may occur daily or according to the seasons. The most common life forms that make up plankton are microscopic and composed mainly of plant organisms (phytoplankton). Animal forms (zooplankton) make up the rest. As divers, we are generally only aware of their existence when we make safety stops and observe the more "gigantic" forms: the macroplankton or megaplankton. To see all the other types we would need a microscope.

teachbesttech.org/best-underwater-cameras/