Osaka Aquarium Kaiyukan

In short

An aquarium that opened on July 20, 1990. With the themes of the "Ring of Fire" (Pan-Pacific Volcanic Zone) and the "Ring of Life" (Pan-Pacific Life Zone), it recreates the natural environments of the various regions around the Pacific Rim, centered around the Pacific Ocean, as faithfully as possible. The building is structured so that visitors follow the route winding downward from the upper floors, touring the exhibits as if diving down into the sea, from freshwater stream creatures to deep-sea life.

• ​"Pacific Ocean" Tank​​: This massive tank pierces through the center of the facility from the 6th floor down to the 4th floor, with a depth of 9 meters and a water volume of 5,400 metric tons, and is home to whale sharks, devil rays, reef manta rays, and other marine life
• ​Different Views per Floor​​: Even in the same tank, the species of creatures and their behaviors differ across the upper, middle, and lower levels. From the lower floors, you can clearly see the whale sharks swimming vertically as they vacuum up their food
• ​Kaiyukan Night Aquarium​​: Starting from the evening, light reminiscent of moonlight shines into the deep blue sea, allowing you to encounter animal movements and expressions different from those during the day

History and Highlights

​Osaka Aquarium Kaiyukan​ is an aquarium that opened on July 20, 1990, on the same day as Tempozan Marketplace. Its themes are the "Ring of Fire" (Pan-Pacific Volcanic Zone) and the "Ring of Life" (Pan-Pacific Life Zone). Centered around the Pacific Ocean—the largest body of water on Earth—it recreates the natural environments of the various regions around the Pacific Rim as faithfully as possible. Its guiding message is that "All things are connected."

The journey begins in the sun-drenched "Japan Forest." The building is structured so that visitors follow a spiral path winding downward from the upper floors, touring the exhibits as if diving down into the sea, from freshwater stream creatures to deep-sea life from the "Japan Trench."

Viewing and Experience Highlights

• ​"Pacific Ocean" Tank​​: This massive tank pierces through the center of the facility from the 6th floor down to the 4th floor, featuring a depth of 9 meters, a maximum length of 34 meters, and a water volume of 5,400 metric tons. Along with whale sharks, it is home to devil rays, reef manta rays, schooling Indian mackerel, and other marine life. The whale sharks have nicknames: the male is called "Kai" and the female is called "Yu." Even when the individual sharks change, these nicknames are passed down.
• ​Different Views per Floor​​: Even when looking at the same tank, the species of creatures and their behaviors differ across the upper, middle, and lower levels. Because feeding for the whale sharks takes place at the water's surface, you can get a powerful view from the upper floors, while from the lower floors, you can clearly see them swimming vertically as they vacuum up their food.
• ​Acrylic Panels Supporting the Giant Tank​​: When the aquarium opened, large tanks utilizing acrylic panels were rare, and an amount of acrylic equivalent to 1.5 times the global annual production of that time was used. The panels of the "Pacific Ocean" tank reach a maximum thickness of 30 centimeters, and an actual panel is on display on the 4th floor along the visitor route.

Tips for Exploring

Many people pause at the corner where the "Pacific Ocean" tank first comes into view right after turning past the "Great Barrier Reef" tank. Because the "Pacific Ocean" tank can be viewed many more times farther along the route, moving a bit further ahead before taking a look is also recommended. In the "Kaiyukan Night Aquarium" starting from the evening, light reminiscent of moonlight shines into the deep blue sea, allowing you to encounter animal movements and expressions different from those during the day. The boarding point for the Santa Maria sightseeing ship is located about 80 meters west after exiting the building, while Tempozan Marketplace and the Tempozan Giant Ferris Wheel stand side by side to the northeast.