A formalin specimen of a megamouth (female) that was washed ashore in Hakata Bay in 1994 is on display.

The building with a seashell motif has a semi-circular design, which is a characteristic appearance of a tent-shaped roof fixed with wires.

[3] The entire building was closed from October 3, 2016 and reopened on April 12, 2017 in order to carry out a major renovation to replace 90% of the aquarium.

[8] The aquarium focuses on the aquatic life of Tsushima's warm current and is made up of a total of 70 tanks.

The highlights are the dolphin and sea lion show and the large panoramic tanks where giant sand tiger sharks swim.

It is a facility for breeding and exhibiting marine mammals, and has two large and small tanks where California sea lions and Spotted seals live.

A columnar aquarium (1.5m in diameter and 2.8m in height) is also installed, and an action exhibition using the habit of seals that rise vertically to the surface of the water for breathing is held.