Water quality can be known from the value of WQI (Water Quality Index), a number that describes water quality based on measurements of water quality parameters. Plankton is an organism whose life is free to hover in the water, its ability to move is limited so that water currents easily carry it away. Benthos is an organism that lives on the seabed or river attached to water sediments (mud or sand). Benthos are used as bioindicators of water quality because life is attached to aquatic sediments. The presence of vegetation also improves the soil's physical, chemical, and biological properties, regulation of groundwater, and others. This research aims to study the characteristics of aquatic ecosystems and their limiting factors, to know the chemical, physical, and biological parameters that determine water quality, learn the techniques for collecting plankton and benthos, identify plankton and benthos, study species and the number of plankton and benthos as aquatic bioindicators.