<；P>；PROBLEM TO BE SOLVED: To provide a method for rearing, storage or transportation of tuna capable of reducing economical and labor load in rearing, storage or transportation of tuna, and to provide rearing water for the rearing, storage or transportation of tuna. <；P>；SOLUTION: The rearing facility for tuna is provided with a swimming tank 10 for tuna. The swimming tank 10 is filled with the rearing water having a controlled salt content by using underground seawater supplied from an underground seawater supply facility 20 and fresh water supplied from a supply pipe 18. A tuna rearing person controls salt content of the rearing water filled in the swimming tank 10 to &ge；25 psu or thereabout and <；30 psu at the time of charging the tuna and, thereafter, lowers the salt content of the rearing water to 20±；3 psu. The tuna is reared by the rearing person by keeping the salt content of the rearing water to 20±；3 psu while periodically measuring the salt content of the rearing water. In this case, the rearing person may lower the salt content of the rearing water to about 15 psu. <；P>；COPYRIGHT: (C)2011,JPO&INPIT
