Population growth increases wastewater production, enhances environmental concerns, and increases wastewater treatment costs. This study aimed to use Anodonta cygnea (freshwater mussels) exposed to some water pollution in a closed cycle to treat wastewater by consuming harmful or undesirable pollutants in water. The results demonstrated that mussels eliminated all microalgae, reduced organic pollutant concentration (chemical oxygen demand removal rate 40% faster than lacked mussels tank), and removed some water hardening minerals such as Calcium (Ca) (more than 77%) and Nickel (Ni) as heavy metal (more than 78%), confirming that freshwater mussels could be helpful in the wastewater treatment cycle. The method can be used as the practical implementation of setting up a semi-natural system for the decentralized wastewater purification relying on the recruitment of mussels. The method also suggests a favorable and eco-friendly treatment mechanism to remove chemical oxygen demand, chemical elements, biological pollutions, and microorganisms.