Due to the efficient uptake of such nutrients as nitrogen and phosphorus by water hyacinths planted in polluted water for purification, the plants become very rich in nutrients and very good as organic maure.
It is so used at the Songhai Centre in Port Novo, Benin Republic and other farms. Also, these nutrient-rich water hyacinths with other wastes are kept in a chamber, they generate heat. A digester theoretically, biogas can be converted directly into electricity using a fuel cell. The energy stored is used for powering an electric generator to produce electricity. In Germany, these engines are advantageous as they do not waste energy. Over 1.8 million cattle dung digesters had been installed in India by the mid 1990s.
Even when the water is not re-used, the water hyacinths are planted in trenches where used water on the farm converges to prevent the odour that would have emanated from water used for purposes such as fish farming.
Farms that have the information thereby use water hyacinths to prevent offensive odour from waste or recycled water rather than chemicals that could be damaging to the environment.
The water hyacinths are also used as organic manure in the growing of vegetables and other crops, and when no longer needed, together with other wastes, the disposed hyacinth plants are used in generating electricity on the farm.