25 Facts about Koi; the elegant fish that enhance any water garden

There is nothing as calming and classy as a home with a well-done water garden, especially when they're filled with Koi. Splendidly colorful in brilliant patterns, these highly revered Japanese fish grow quite large and can even outlive their owners.

Despite the prevalence of Koi ponds in gardens, homes, and office lobbies, relatively little is known about them for the common person.

So instead of covering the practical details of how to install a koi pond DIY or tips for maintaining one at your property, we thought we’d highlight some facts about these amazingly majestic fish.

25 facts about Koi:

1. Koi originated in Japan in the 1820s, and keeping them is a longstanding tradition and national pastime. 

2. Despite their impressive aesthetic, Koi are nothing more than domesticated common carp (Cyprinus carpio), only selected and interbred over the centuries for their beautiful color, size, and other characteristics. 

3. While often referred to as "Koi fish," the correct name is just "Koi." (Just like "lion," or "dolphin, etc.)

4. They are a freshwater fish and cannot survive in salt water.

5. Still to this day, Koi symbolize wealth, prosperity, friendship and love for the lucky owner. In Japanese culture, giving a Koi to someone as a gift means you’ve granted them good luck.

6. Appearing in a kaleidoscope of designs, patterns, and hues, Koi commonly have black, blue, red, orange, cream and yellow colors.

7. No two Koi are exactly alike, as there are many subtle variations based on color, pattern, spots, size or absence of scales, metallic appearance, etc. But there are 22 commonly-recognized categories of Koi.

8. Female Koi are more social, personable, and playful than males of the species.

9. The typical Koi lives up to 25 to 35 years with proper care, a long time for an animal. However, Koi have been known to live past 100 years or even up to 200 years in some rare cases! Some Koi live so long that they are passed down from generation to generation, treated as a cherished family heirloom.

10. The record for the longest living Koi goes to the legendary Hanoko, a Japanese fish that survived for 226 years! In fact, Hanoko was born in 1751, five years before Mozart was born, and didn't pass until July 17, 1977, shortly after its 226th birthday!

11. You can determine a Koi's age just by counting the rings around their outer scales, with each ring representing two years of their life.

12. Koi are actually not herbivores like some species of fish, but omnivores (consuming both plants and animals), eating other kinds of fish and their eggs, as well as rice, corn, lettuce, watermelon, and peas.

13. The price of these colorful fish varies widely, but generally, they are not expensive as infants, but then increase in value as they grow, with their price escalating the longer, heavier, and more colorful they become.

14. While young Koi often sell for $20 or so at a pet store, the well-matured larger fish sell for up to $50,000 or more!

15. In Japanese society, there's a centuries-old tradition that if someone can present a Koi that is four feet long, they will win a $1 million prize.

16. Koi grow rapidly in their first couple years, and mature Koi will sprout to two and even three feet long and weighing a sizable 35 pounds on average. 

17. However, these fish will only grow as big as their container or water source allows, so Koi that are cramped should be transferred to bigger ponds.

18. Most people don’t realize that Koi and goldfish come from the same descendant centuries ago. In fact, a Koi and a goldfish can still mate these days, but their offspring will be sterile.

19. These fish are intelligent and can learn to recognize any human being that feeds them, and can even be trained to eat directly from his or her hand. They're also social and affectionate creatures and will give puckering "fish kisses" to the objection of their adulation.

20. For that reason, Koi prefer to cohabitate with other Koi, living in schools. But they can also live perfectly well sharing their pond with other fish, as long as they aren’t aggressive species. However, Koi will eat the eggs and young fry of other fish, at least until some color appears on their bodies.

21. But Koi have several natural predators, themselves, such as raccoons, otters, badgers, birds of pretty like hawks, snakes, cats, coyotes, and even the family dog! 

22. Koi don't have stomachs, so they digest their food throughout their gut or intestines, and it usually takes then about 4 hours to digest their food completely in warm water.

23. To reach their maximum size, Koi need to be fed about every 4 hours, so automatic feeders on a timer come in handy for owners.

24. Koi fish need to live in temperate climates, but they can survive in areas with cold winters. In fact, when the temperature drops, Koi will hibernate, swimming to the bottom of the pond (where the water temps are a little highest) or burying themselves in the mud and remaining dormant until the spring thaw.

25. If it's too hot and their pond is exposed to all-day direct sun without enough rock ledges and places to find shade, Koi can get dangerous sun burns.