You don't. You put it in a pond. Koi grow to over 24". To keep one in a bowl would be terribly CRUEL!
A fish bowl is not a solution its what you keep your goldfish/ beta fish in :P
it depends how big the fish bowl is
The size of the koi will depend on many factors such as what type of koi it is, how much and what you feed it and the size of the aquarium or pond you keep it in.
Koi fish Koi fish
The cheapest way to keep a goldfish is to keep it in a fish bowl.........as long as the bowl is big enough the fish will be happy there.
Betta
Koi fish can live in almost any country. Koi are thought to be originally from Japan. Many people have outdoor fish ponds in which Koi are the dominant fish.
I guess you mean Puffer fish. If so, then the answer is definitely NO! IMO there is no fish that should be kept in a fish bowl.
No
If you mean a bowl like a glass bowl the size of your head that you keep as a centerpiece, no. Well, you can, maybe, while they're babies, if you have a filter, aerator, and don't mind your fish dying in infancy. The only fish that can really be kept in bowls are bettas, and even then it's a good idea to have a filter and heater. Koi were developed to have a broad colourful back so that they look good when viewed from above. They are POND DWELLERS and grow to over 2feet long. To put one in a fish tank would be CRUEL!! To put one in a Bowl would be TORTURE!!!
a fish, a koi carp
The best candidates are Betta fish and Paradise Gouramis