Productive artificial aquatic ecosystems for recycling of anorganic nutrients in wastewater and production of zooplankton and plants as food for fish stocking

The phytoplankton-zooplankton system is an important part of the aquatic ecosystem and a basic source of food for fish in natural lakes and rivers. It is also the main transformer of anorganic nutrients to organic material. Those organisms have a high productivity and are able to adapt to changing environment conditions by varying the size of their population. Zooplancton is well suited to serve as animal protein for fish stocking. In this experiments the possibilities of practical application for elimination of anorganic nutrients out of greenhouse culture wastewater was testet. In a preceeding experiment we tested the possibilities of a low technology continuous culture of Algae and daphnids was tested. The main experiment is one step of a aquaculture pilot plant [1,2,3]in wich plants and fish for food purpouse is produced. In this presently running main experiment we test the operation of smal aquatic ecosystems (300 1 each) with different planctonic crustaceas and submersed vascular plantsare cultivated for use as fish feed.