Although the Kaiyukan Aquarium is located right on Osaka Bay, it is truly a case of "water, water everywhere, ne'er any drop to drink" for the 39,000 fish and 580 species of other sea creatures kept there in 15 large tanks.
The aquarium in Osaka's Minato Ward may boast a world-class range of exhibits, but its denizens of the deep wouldn't last long in water taken from off their doorstep -- just as no one now dares even to swim in the expansive bay.
As a result, the original 11,000 tons of seawater required when the aquarium opened 14 years ago came from off Kochi Prefecture, on the Pacific coast of Shikoku. Now, even though ferries deliver several 300-ton loads of ocean water every month to refresh the aquarium's marine environment, the condition of the water in their tanks is still the single most important consideration for the aquarium operators.