WATER RECYCLING AQUACULTURAL EQUIPMENT AND ITS APPLICATION

摘要

An aquaculture tank assembly is provided comprising an open topped tank (1) having formed in a lower region thereof a biofilter (3), a water outlet assembly (4,5) located at or towards a bottom of the biofilter, a protein skimmer (7), and a water return arrangement (11,14) for returning water from the protein skimmer to the aquaculture tank. At least one, and typically a series of upwardly extending airlift pipes (15) is provided for lifting a portion of the water that has operatively passed through the biofilter to an elevated position within the tank by an airlift process so as to return said portion of the water directly to an upper region of the aquaculture tank and simultaneously aerate it. The balance of water that has operatively passed through the biofilter is passed through the protein skimmer prior to return to the aquaculture tank. Preferably about 25 to 50% of the recycled water is passed through the protein skimmer with the balance being recycled directly from the bottom of the biofilter by way of the upwardly extending airlift pipes. In a preferred form a solids collection facility (23) is provided above the biofilter for collecting and enabling periodic discharge of solids including faeces.