The study compared how well Zizania latifolia and Acorus calamus can clean up dirty water. Both plants did a good job in eutrophic water. When grown alone, they removed a lot of nitrogen and phosphorus from the water. Acorus calamus was better at cleaning up phosphorus than Zizania latifolia. When grown together, the two plants were just as effective as when grown alone. Overall, both plants and their combination were equally good at purifying the water.