CONCENTRATED NATURAL SEAWATER OBTAINED BY CORRECTING COMPONENTS THEREOF AS SUITABLE FOR CLOSED CIRCULATION

PROBLEM TO BE SOLVED: To provide concentrated natural seawater made as having blended components suitable for being utilized as rearing water by eliminating the mixing of sundry bacteria and impurities of the natural seawater and suitable for closed circulation adaptable to a rearing environment and economic efficiency.SOLUTION: The rearing water is prepared by physically filtering the natural seawater adjusted to have a specific gravity of not less than 1.06 and less than 1.21 by a salt production process of salt field concentration with sun and sea breeze, adjusting its useful components, then subjecting the components to heat treatment at 85°C for 10 min, adjusting its specific gravity after normal temperature cooling, to a concentrated standard specific gravity of plus or minus 0.03, subjecting the components to activated charcoal filtration, adding a calcium compound and an iron sulfate to the concentrated seawater packed after a viable bacteria test and adjusting the specific gravity after dilution to 1.023.