Very rarely, I use an electron microscope. Electron microscopes are much more powerful, but more difficult to use so they aren't good for most of my day to day needs. It takes too long to get images. The microscopes have TV cameras on them. That's nice for allowing lots of people to see what's on the 'scope at once.
Many small minnows eat a lot of zooplankton.
Maybe the most famous plankton eater is the sperm whale, that strains zooplankton like krill out of the ocean water. These big creatures all depend upon food items that, in lakes and the oceans, come from tiny plants and tiny animals. These kind form these surface blooms because they have little gas vesicles, things that are like baloons. They get bouyancy from those vesicles, which allows the algae to get up in the light. The vesicles make the algae move up and down in the water like a submarine, using the same physical principles to do so.