How big is the daphnia?

Daphnia, commonly known as water fleas, typically range in size from about 0.2 to 5 millimeters in length, depending on the species and environmental conditions. They are small, transparent crustaceans that play a significant role in freshwater ecosystems. Their size allows them to thrive in various aquatic habitats, where they serve as a vital food source for many fish and other aquatic organisms.