In the Pearl River Delta, Koi is known as an "auspicious fish.” Both the park and private gardens can often see the graceful Koi. I did not expect that Koi was so popular in Thailand. The following Koi are still in their own building!
This was once a large 11-storey shopping center in Bangkok, capital of Thailand. It was burned down in 1999 and eventually became an abandoned building. Due to the severe damage to the top, the rainwater has been stored for a number of years, and the large shopping malls of that year gradually became ponds. Later, more people raised fish here. The few Koi fish fry that were initially put into use have now grown in size. Thousands of Koi have completely occupied this building. It is spectacular! Let's take a look at this wonder!
Source: theverge
https://www.theverge.com/2014/6/30/5856856/abandoned-mall-in-bangkok-has-been-overtaken-by-fish