Without its usual crowd of spectators, Kaikyokan’s sunfish essentially started to fall into a deep-sea depression.

The Shimonoseki City Aquarium in Japan's Yamaguchi Prefecture needed to undergo renovations, and temporarily closed to the public in December, 2024. Staff said the aquarium's sunfish lost his appetite after a week without guests.

A sunfish at a municipal aquarium undergoing renovation in this west Japan city became unwell, but recovered after its tank

An aquarium in Japan has come up with a unique and out-of-the-box idea to cheer up its lonely resident sunfish after the facility closed for renovations.

The Kaikyokan Aquarium in Shimonoseki, Japan, which is undergoing renovations, revealed in a post on X that its staff had to think out of the box to help one of its sunfish struggling with the change.

SHIMONOSEKI: A lonely ocean sunfish in a Japanese aquarium, which seemed to be missing its human visitors and caretakers during the facility’s closure, has found a surprising source of comfort.

Staff members believe the sunfish stopped eating when the aquarium was temporarily closed because it was lonely.

"When an aquarium in Japan closed to the public for restorations, the aquarium's beloved sunfish grew lonely without visitors and lost its appetite — until aquarium staff pasted cutouts with photos of human faces onto the tank," the video caption explains. That's right — they made people! Have you ever seen something so sweet?

A solitary sunfish at an aquarium in Japan lost its appetite, began banging into the side of the fishtank and appeared unwell days after the facility closed last month for renovations.

The Japanese aquarium posted a photo on its official X (formerly Twitter) account on 3 January, showing the sunfish named Mambo swimming in its tank, surrounded by cutouts of smiling faces and staff uniforms on hangers stuck to the glass. The heartwarming but hilarious post has gone viral, receiving more than 12.5 million views and comments.

Within a few weeks of closing for renovation, their 30-plus kilogram ocean sunfish began exhibiting strange behavior.

An aquarium in Japan closed Dec. 1 for renovation work, much to the apparent dismay of a lone sunfish. It missed people and stopped eating.