The study looked at how different underwater plants can clean up nitrogen and phosphorus from water. They tested eight common plants and found that Vallisneria denseserrulata was the best at removing these pollutants. The plants work together to clean the water, and bacteria living on the plants help with the process. Certain bacteria, like Cupriavidus and Rhodobacter, play a big role in cleaning the water. Overall, underwater plants are good at purifying water, especially Vallisneria denseserrulata and Vallisneria natans.