Can a 45cm wide aquarium breed more than 50 koi?

Can raise koi fish up to 20 cm. No matter how big it is, it’s not that you can’t keep it, but it’s bad for the fish. In addition to good food and drink, koi also need a large home. A small house will limit koi growth and can cause tail fractures. Many finished aquariums at home are 20 centimeters thick, more than a meter high and 80 centimeters wide, giving the illusion that they can raise very large koi. In fact, koi breeding depends on the smallest size of the aquarium. At least ten centimeters larger than the fish, including head and tail. My koi has been raised since I was a child. It was only ten centimeters when I got home. I used a 50 cylinder tank, and the thickness of the 50 cylinder tank is 30 centimeters. As the fish got bigger and bigger, I moved to aquarium of 60, then to an aquarium of 80 after a year. My koi are dragons and phoenixes. Originally their tails were so big, like a skirt, but now the fish have grown up. Now the thickness of the 80 tank is also 40 centimeters. Although the tail is soft, the fish's tail is no longer long and the bottom is uneven. When the koi turns around, its tail always sweeps the tank wall. or the pipeline in the water. I'm thinking of customizing an 80cm square cylinder, otherwise this beautiful big tail will be of no use. Therefore, it is recommended to buy small koi, such as 10 centimeters, five or seven are enough (the custom of breeding koi is not to feed them in even numbers once a day or every other day) . I only feed it once a day and it grows very quickly. I need to upgrade to a larger tank in two or three years.