Algafilm

AlgaFilm treats wastewater with a standing field of cone-shaped carriers that grow algae biofilm. Effluent is sprayed over the cones, algae and bacteria pull the nitrogen and phosphorus out of it, and the biomass is harvested. Those nutrients are what drive eutrophication and the algal blooms that close beaches and suffocate lakes, and the conventional way to strip them out is energy-hungry aeration that smaller municipalities and farms can't justify.

The Algae Forest runs without chemicals, on a fraction of the electricity aeration demands and a fraction of the land a treatment pond needs, and the algae pull carbon out of the air as they grow. Nutrient pollution is one of the least glamorous environmental problems there is, and it has stayed unsolved for the towns that most need an answer largely because the answer cost too much to run.