A study tested a system using wetlands to clean up wastewater from tanneries. They used plants called Phragmites australis to remove nitrogen, phosphorus, boron, and chromium from the water. The plants were good at absorbing phosphorus and chromium, but not as effective for nitrogen and boron. The best results were seen with a 3-day treatment time. The plants absorbed nitrogen and phosphorus well in their above-ground parts, while boron was mostly taken up by the roots. Chromium was absorbed best at the 3-day treatment time. The type of soil in the wetland also helped remove nitrogen and boron. Overall, using these wetlands with Phragmites australis could help reduce pollution from tannery wastewater, especially for phosphorus and chromium.