There are basically four types of algae, based on their color: green, blue-green, red, and brown. Green and blue-green algae are found in freshwater as well as saltwater. Red and brown algae are found ...

On the right side of the cover, it is daytime—and we can see two kinds of algae in the water around the boat. One type is microalgae, which can only be seen with a microscope. Macroalgae, on the other ...