In a controversial experiment in Florida, researchers are stocking King’s Bay with floating pens of water hyacinth (Eichornia crassipes) to reduce algal blooms. Water hyacinth was removed from the bay beginning in the late 1950s, but Hydrilla replaced it and now algal blooms have become an issue in the lake. Water hyacinth is good at removing pollutants from water and shading out algae. In addition, manatees love it!
The pens also contain two other non-native species (called native in the original article), water lettuce and frog’s bit, considered less invasive by the some, but the article does not address whether these two plants would serve the same function as the water hyacinth.