Koi vs Goldfish: Difference and Comparison

When we visit a mall or a restaurant, we notice small attractive fish in aquariums. These fishes in the aquariums grab our attention with their bright body colors.

The most common color which we find attractive is deep orange. Usually, these colors are present in goldfish. Goldfish is orange and shiny.

Goldfish and Koi fish are similar fishes in terms of appearance. These are used majorly for decorative purposes.

Key Takeaways

  1. Koi are larger, more colorful, and have elongated bodies than goldfish.
  2. Goldfish can thrive in smaller ponds and aquariums, while koi need larger spaces to accommodate their size.
  3. Koi tend to be more expensive and require more maintenance than goldfish.

Koi vs Goldfish

Koi, or Nishikigoi, are decorative fishes of the Amur carp species. It is a variety of fish originating from Japan which symbolizes prosperity and luck. Koi fishes require a high level of maintenance and live up to 35 years. Goldfish is a freshwater species originating from China. They require a moderate level of maintenance and have a lifespan of up to 15 years.  

Koi vs Goldfish

Koi fish originated domestically from Japan. Common species of these koi fish are known as carp. Koi fish are the colored and beautifully patterned subspecies of Amur carp.

It’s said that koi fish is originated from the species of Cyprinus Carpio (Carp). Koi fish have barbels, and most people recognize koi fish with these barbels.

Goldfish are also originated from East Asia and were developed in China. Similar to koi fish, goldfish are also originated from species of Carp.

The selective breed created goldfish, the Prussian Carp, which is a light olive green-colored eatable fish. Goldfish are more than a thousand years old species.

Then they were developed to different color mutations.

Comparison Table

Parameters of ComparisonKoiGoldfish
Originated speciesKoi fish is originated from the species, Cyprinus Carpio.Created by crossbreeding of Prussian Carp.
Typical length and weightKoi fish are 20 to 30 inches long and weigh about 10 to 15 Kgs.Goldfish are 2 to 6 inches long and weigh about 90 to 200 grams.
HabitatHigh maintenance is required for koi fish.Moderate maintenance is enough for Goldfish.
Body StructureElongated body.Could be elongated, round, and even egg-shaped
LifespanKoi fish have a lifespan of around 20 to 35 years.Goldfish have a lifespan of around 10 to 15 years.

What are Koi?

Cyprinus Carpio, known as Carp, is a species of fish originally found in East Asia, used as food fish. Koi is originated in Japan.

Also Read:  Cockroach vs Beetle: Difference and Comparison

These fish are color variants of Amur Carp, used for decorative purposes over the years. “Koi” is a Japanese word.

This fish breeding process was started in the early 19th century. They are known for their bright and attractive colors and pattern styles.

Koi fish has an elongated body structure.

Koi fish are intelligent creatures who can be trained to recognize their owners. Japanese consider koi fish as symbols of strength and endurance.

They use koi fish for ornamental purposes in their ponds. We have approximately 20 different koi fish variants. Koi fish can live for over 100 years.

The average lifespan of koi fish is around 35 years. The oldest koi fish recorded is around 220 years. They grow about 3 to 4 feet long.

Usually, koi fish are maintained in ponds. As the size of the koi fish ranges from 25 to 30 inches, aquariums can’t facilitate koi fish.

They require well-oxygenated freshwater ponds with low waste. They can even tolerate extreme temperatures.

The moderate conditions for koi fish dwelling places are temperature ranges around 60 to 80 Fahrenheit. And pH of the water in the tank should be around 7.0.

koi 1

What are Goldfish?

Goldfish are created by crossbreeding of selective species of Prussian Carp. Goldfish also belong to the carp family.

Goldfish are said to originate from East Asia, China. Goldfish are small and round ornamental fishes. Goldfish do not have any barbels.

Goldfish are seen in various patterns, scales, and tail forms. Goldfish can be observed in different colors and body structures with selective cross-breeding of fish.

Goldfish are sensitive fish. Most of the goldfish are commercial and used for decorative purposes only. Their cross-breeding is also not easy.

Commercial goldfish are created to live indoors. They are sensitive and require regular attention.

Also Read:  Nucleus vs Nucleolus: Difference and Comparison

And there are some fishes which can dwell in outdoor ponds also. Goldfish have more hunger.

Always looks for food and consumes more fish food. The typical life span of goldfish is about 10-15 years.

The size of goldfish is around 2 to 5 inches, so they are mostly seen in small aquariums, in houses, and in public places.

Goldfish maintenance is not that easy, it’s expensive and includes regular checks. They require a well-maintained tank.

With utmost care and the best diet, goldfish can survive up to 15 years. They should not be stressed. Stress leads to loss of appetite and illness in fish.

Regular filtration and water changes should well maintain their tank. Water should be warm, and good pH levels are to be maintained.


Main Differences Between Koi and Goldfish

  1. The main difference will always be the origin of the species, and koi fish is bred from Cyprinus Carpio(referred to as common carp). In contrast, Goldfish are created by selective crossbreeding of Prussian Carp.
  2. Both the fish look alike during their initial days. But as they grow older, koi fish have small sensory organ projections on the mouth and barrels, but goldfish don’t.
  3. Koi fish and goldfish also differ in their fins structure too. Koi fish have attached dorsal fins. And goldfish have detached dorsal fins.
  4. We have around 200 varieties of goldfish with different fin styles, colors, eyes (bubble eye, scope eye), and body structures. While koi fish are long fish, we can’t find many varieties of koi fish comparatively.
  5. Koi fish are massive and larger compared to full-grown goldfish. That’s why koi fish are placed in ponds and big aquariums. Whereas small indoor aquariums are enough for goldfish.
Difference Between Koi and Goldfish
  1. https://pubs.acs.org/doi/abs/10.1021/ja509340c
  2. https://www.journals.uchicago.edu/doi/abs/10.2307/1538211

Last Updated : 26 June, 2023

dot 1
One request?

I’ve put so much effort writing this blog post to provide value to you. It’ll be very helpful for me, if you consider sharing it on social media or with your friends/family. SHARING IS ♥️

16 thoughts on “Koi vs Goldfish: Difference and Comparison”

  1. The information provided here is really helpful in understanding the differences between koi and goldfish in terms of everything from maintenance to lifespan.


Leave a Comment

Want to save this article for later? Click the heart in the bottom right corner to save to your own articles box!