This is the viral video of a greedy Japanese koi carp that has eaten so much food it looks more like a coloured balloon than a fish.

The video was shot at a public pond located at the Baotu Spring in Jinan, in China’s Shandong Province.

Koi are a popular addition to ornamental ponds around the world, and especially water gardens, and they are actually a variety of the common carp.

They also have a tendency to put on weight when given a regular diet of high-carbohydrate fish food, which can significantly shorten their life spans. A koi carp that is given a healthy diet can sometimes live for more than 200 years, with the oldest ever recorded reportedly 226 years old.

The huge fish amazed visitors with one saying: “I thought the fish was flat last time, but I had no idea that it would be able to get even fatter.”

Another named Mr Zhou, who was apparently feeling hungry, said: “Is it illegal to steal it?”