From the Blending Tank water flows to the Greenhouse. Higher plants on the surface of the Solar Tanks and Solar Ponds, with their root masses reaching down into the water column, take nitrogen and phosphorous from the waste stream to promote leaf and flower production. The extensive surface area of the root systems filters solids from the wastewater and provides extensive microsites for microbial attachment. Very large populations of zooplankton also inhabit the root mass. Bacteria, algae and higher plants metabolize components of the waste stream.
Organic nitrogen is mineralized into ammonia.
Ammonia is oxidized into nitrates. BOD is degraded. Nitrates, ammonia, and soluble orthophosphates are taken up directly by green algae and higher plants. Snails, zooplankton and other animals feed on solids. Following treatment in the Solar Tanks and Solar Ponds, residual biomass and recalcitrant solids are removed from the process stream by clarification.