The goal of the study was to clean up polluted wastewater from Batik production using water hyacinth and water lettuce. The researchers found that these plants were able to significantly reduce levels of ammonia and chromium in the wastewater. Water hyacinth reduced ammonia by 78.36% and chromium by 63.76%, while water lettuce reduced ammonia by 73.13% and chromium by 83.39%. This shows that water hyacinth and water lettuce are effective at removing pollutants from Batik wastewater.