METHOD FOR GROWING FISH IN CLOSED BASINS Russian patent published in 1997 - IPC

FIELD: production of fish in natural and artificial basins. SUBSTANCE: method involves laying natural zeolite on dry bed of basin in an amount at least equal to 100 kg/hectare to reduce contamination of water with heavy metals, which may be present on basin bed as well as may be carried by water delivered from source; filling basin with water; putting young fishes into basin; feeding young fishes and controlling and regulating hydrochemical conditions in basin. To do that, ammonia and heavy metal content in water is determined. When content of mentioned components exceeds allowable values, zeolite is introduced at the rate of (100-150) n kg/hectare, where n is basin depth. Zeolite is added to inhibit the process of contamination of basin water with ammonia ions and reduce concentration of ions to optimum values. EFFECT: increased efficiency by controlling fish keeping conditions and providing stabilized oxygen mode. 1 tbl