It’s incredible to discover that a common ornamental aquarium fish grew to enormous proportions and became the world’s biggest goldfish.

Yes, you read it correctly. But what’s more surprising is that it can grow almost ten times its captive size.

A more prominent theory says that there is no calculative length of a big goldfish. It continues to grow as long as it lives, although the growth speed is slower and depends on multiple conditions.

These are small glaring fishes of about 1 – 2 inches in length, mostly in red, orange, or yellowish color, and look extremely beautiful in aquariums.

But fish keepers rarely know that if proper care and environment is provided, then this decorative aquarium pet holds a hidden tendency to increase its size to a great extent.

We’ll decipher the factual truth regarding the World’s largest goldfish and tell you how big they can get as per their ability.

When did the World Recognise the Existence of Big Goldfish?

Goldfish, which were once bred as an ornamental aquatic in the East Asian countries almost a thousand years ago, became popular in the Western World for their beauty and glare. It reached Europe in 1620 and came to the USA after 1850.

These fishes became a household friend of almost every American & European, as these were among the first-ever introduced fish from a foreign land.

As the craze for petting them diminished, these were occasionally observed to be released in ponds lakes.

In the later years, these goldfishes have regularly been found in the local water bodies. It is probably because the owners no longer wanted to hold a giant size goldfish, which was once a cute little aquatic.

A credible study by experts in 2015 discovered about 4000 such large goldfish at a lake in Colorado. And a similar experience was observed at Lake Tahoe, border of Nevada & California, where the researchers found 4 – 8 inches of extraordinarily longer goldfish.

What is the World Record for Biggest Goldfish?

Goldfish has mostly been praised for its glittering designer scales and are underestimated regarding the monstrous outlook it can attain. So there has been a continuous enthusiasm for finding the world’s largest goldfish. However, most of the time, there are misidentifications about the species.

Here is a list of some most reliable claims about the goldfish that reached their maximum size. Let’s find out if they were the biggest goldfish.

Mysterious Discovery in America, by 33 Years Old Fisherman Jason Fugate

Length:91 cm
Where:Brainerd Lake, USA

In 2019 a story floated in the media about finding a hundred-year-old big goldfish at a lake in America. But Dr. Alec Lackmann from North Dakota State University revealed that this 36 inches long yellow fish was not goldfish but a genetic mutation of bigmouth buffalo fish.

False Claim by Angler Raphael Biagini in France

Length:Size of a big dog
Where:South of France

Another story came in 2010 when a fisherman named Angler Raphael Biagini caught the biggest goldfish in France, weighing like a three-year-old girl. But this was actually an orange koi carp.

Angler Raphael Biagini caught the biggest goldfish in France
Image Credits: Flickr Creative Commons

Biggest goldfish in America Found by Ty Houck

Length:38.1 cm
Weight:9 lbs
Where:South Carolina, USA

The biggest goldfish ever caught in the USA was 15 inches long, weighing about four kilograms. It was found in Oak Grove Lake Park, Greenville, during a regular fish population survey by the Wildlife Officials under Ty Houck. The team could not find any other goldfish in the lake.

See also  Black Algae in Your Fish Tank: 3C’s (Causes, Control, and Care)

“Goldie,” “Simply Amazing” Goldfish from England

Length:40.6 cm
Weight:2 lbs
Where:Kent, England

A goldfish was purchased by an old lady Ada Shaw when it was one inch in length. With proper care and a suitable environment, the fish, named Goldie, grew to be Britain’s second-biggest goldfish reaching about 15.7 inches in length. The marine biologists sized it and said, “simply amazing.”

Billy the Big Goldfish of the UK

Length:41 cm
Weight:5 lbs
Where:Poole, UK

Soon after identifying “Goldie,” creating a World record for the biggest goldfish, Nick Richards, a college student from Camberley, caught the largest goldfish in the UK at a lake in Poole, Britain. He named the fish “Billy,” which was 16 inches long and weighed five pounds.

The World’s Largest Goldfish in the Netherlands

Length:47.4 cm
Where:Hapert, Netherlands

Leaving behind these large goldfishes, the Netherlands holds the Guinness record of having the World’s biggest goldfish, which was 18.7 inches long. It was sized from tail to mouth, on 24th March 2003, at Hapert. Joris Gijsbers was the owner of this fish.

Factors Responsible for a Goldfish’s Bigger Size

Goldfish belongs to the Cyprinidae family and prefers to live in freshwaters. They were originally a mutated species and developed during selective breeding of Prussian & Crucian Carp in early China.

Traditionally, the carp category of fish has an average length greater than 50 inches. The Asian Carp that were bred artificially in East China naturally developed the golden-yellow color. With its beauty and symbolism of fortune, these were restricted to the royal family.

Though the initial purpose was to farm fish for the food industry, the carps, with their ability, formed the peculiar orangish & yellow shade from the regular grey and silvery color.

Later the fish became popular around the World as an aquarium elegance, and petting them in glass cases would only let them increase about 1 – 2 inches.

But what could be the possible reason behind this terrible enhancement in size?

The Prominent Factors Affecting the Growth of a Goldfish

Being a member of the carp fishes, the goldfish possesses the quality of size enhancement if left in open water. A suitable environment lets them grow longer to become bigger goldfish.

They are invasive in nature; hence, they easily adjust to the local water conditions and find their feed to live and rule the territory.

The water parameters that allow goldfish to grow larger are mentioned below.


The movement of the fish is one of the major factors affecting its growth since they lengthen more in the wild. But if you are keeping them in captivity, give them a minimum of twenty gallons of tank space. Bigger the room better the growth.

See also  Dropsy: Is This What’s Making Your Goldfish Look Fat?


They need alkaline and protein-rich food twice or thrice a day at scheduled intervals. Over-eating can be harmful, and hence they should only be allowed to eat whatever they can in the initial two minutes.


These are cold-water fishes and stay comfortable at 18 – 24 degrees Celsius, but the temperatures should not go below the moderate level.


A healthy freshwater environment is essential for optimum growth rate. This fish is a habitual waste creator, so if they are being bred in an artificial tank or pond, then make sure to keep changing 25% of the water every seventh day and 50% of water after the 30th day.

Are Wild Goldfish Bigger Than Those in Captivity?

Whether it is a goldfish or any other aquatic, they can only increase to a certain level if kept in a surrounded region.

Certain fishes are genetically predisposed to not grow huge in a larger environment. On the other hand, the goldfish rejects this hypothesis, which has long been unknown to humans.

All they require is food, moderate temperatures, and mobility to attain the size of a big goldfish.

They can easily adapt to the local water conditions and feed themselves over larva, live warms, shrimps, or even green leafy plants. They continuously invade the area and keep growing in length during their lifespan at a slow pace.

How Big do Goldfish Get on an Average?

As recorded by fishkeepers, the average size of a goldfish is around 2 – 3 inches. They found that with the provision of a proper diet, and fulfilling other favorable conditions, they can even increase up to 5 – 6 inches in an aquarium.

But if a healthy goldfish is released in ponds or lakes and is not predated for a long time, it can grow up to an average length of 12 – 14 inches.

How Fast do Goldfishes Grow?

The goldfish has been under observation by aquarists for hundreds of years. They are selectively bred to form multiple shades of reddish to yellowish.

A juvenile grows faster than the adult goldfish since the fish reaches its adult age in almost six months. It grows about two inches in completing six months, but later the growth rate slows down to one inch in the next six months, followed by an inch per year in the later years.

If they are kept in a closed condition but fed with proper food items and provided with suitable water temperatures, they will increase very slowly but won’t exceed six inches.

But they literally do not stop growing in length and keep increasing throughout their lives until they get a suitable environment.

And if released in open freshwaters, they can comfortably roam around, which works as an exercise to gain body length, particularly for this fish.

They only live about 6 – 7 years in a fish tank, but in the wild, they may even stay alive up to 30 years and hence can achieve a monstrous size comparatively.

Which Goldfish Breeds are the Biggest and Longest of all?

The goldfish was originally discovered or bred in Imperial China, which later reached Europe and America after many years of its invention.

They are the first to claim and identify around 300 typical goldfish varieties, while Americans are far behind in recognizing less than 150 yet.

See also  Exploring the World of Fish Spawning: How do Fish Breed

The goldfish is differentiated over parameters like-color, shape, length, fin-type, and eye structure. The theorists say that out of those hundreds of pre-defined species, there are only 15 identifiable real goldfish categories, while the rest can be summarized into them accordingly.

Here is a list of all the biggest goldfish species:


oranda goldFish
Oranda GoldFish
Color:Orangish and White
Approx Size:30 – 40 cm
Body Type:Egg-shaped
Tail Type: Double, Long, and Fanning

The biggest goldfish breed ever recorded to date is the Oranda goldfish, which is a mix of red & orange colors with white at the base. They are commonly called red cap orandas or brain fish, having a big win over the head to cover the cheeks and gills, giving them a “puppy look.”

These are the World’s most giant goldfish, with an average size of twelve inches and gaining a maximum length of up to 16 inches.

Visit for detailed information on Oranda Goldfish, Care, Types, and much more.

Veiltail Goldfish

veiltail goldfish
Veiltail Goldfish
Color:Yellowish but found in many other colors
Approx Size:20 – 30 cm
Body Type:Egg-shaped
Tail Type:Double, Very Long, and Free-flowing

These fishes are also known as Broadtail, as they present a big fanning tail-fin. The fins are so long that they hangout and make them a slow swimmer. The fish has an average size of 8 inches and can grow up to 12 inches in length.

Jikin Goldfish

jikin goldfish
Jikin Goldfish
Color:Pure White with Red fins, tail, gills, and mouth
Approx Size:31 cm
Body Type:Streamlined
Tail Type: Double split to create four fins in cross design from the back

The fish is also called 12 Red due to the twelve specific body parts in red color, including lips, dorsal fin, two gills, and four pairs of fins. They have a long white body with a short peacock tail and acquire approx—12 inches of body size.

Watonai Goldfish

watonai goldfish
Watonai Goldfish
Color:White body with Reddish fins and tail, Orange head.
Also available in other colors
Approx Size:32 cm
Body Type:Streamlined
Tail Type: Double, Long Fan-tail

They are a cross-breed of Ryukin and Wakin fishes. They are hardy in nature and look similar to Comet goldfish, except for the double tail. They easily adjust in the open waters and can elongate upto 12 inches.

Wakin Goldfish

wakin goldfish
Wakin Goldfish
Color:Wide pattern of Red and White
Approx Size:31 cm
Body Type:Streamlined
Tail Type:Split Double

They have a pair of tail-fins and anal-fins and are known to create many fancy goldfishes available. They can grow about 12 inches in length, while the red and white coloring looks similar to koi fish.

Common Goldfish

common goldfish
Common Goldfish
Color:Pure or mix of colors like Orange, Yellow, Red, Black, Blue, or Brown
Approx Size:31 cm
Body Type:Streamlined
Tail Type:Single

As the name suggests, they are easily found in pet shops and ponds. They are available in bright, electrifying colors with sharp spined tails and small lobes, and they can increase upto a length of 12 inches.

Comet Goldfish

comet goldfish
Comet Goldfish
Color:Dark Orange to Red with a White mix
Approx Size:36 cm
Body Type:Streamlined
Tail Type:Single, Long, and Forked

These goldfishes were originally developed in America and are available commonly. Though similar to common goldfish in looks, it has long fins and a tail almost the size of its body. These are fast swimmers and are among the longest goldfish to reach about 14 inches in max length.


shubunkin goldfish
Shubunkin Goldfish
Color:Like a mosaic stone, it has a White base with a mix of Red, Orange, Black, and Blue
Approx Size:35 cm
Body Type:Streamlined
Tail Type:Single, Long, and Forked

The unique coloration typically differentiates it from the comet and common goldfish. The calico pattern of colors with metallic scales has a mix of other shades.

Three popular Shubunkin are available: –

  • American Shubunkin has a long tail. They are also called Ribbon-tail Shubunkin.
  • Bristol Shubunkin has a forked tail with a slightly longer length and “B” shaped lobes.
  • London Shubunkin has a small round-shaped tail.

These fishes can grow up to 14 inches in size.

Factual Analysis

The goldfish has been a favorite living room decoration in the aquarium for many years, and people still admire them for their unique features. But the fish possesses the ability to enlarge to a great extent.

Hence instead of disposing of them in an open environment, one should consider contacting a local pet shop or veterinarian to transfer the liability. It disturbs the local environment in multiple facets by either eating the eggs of the natives, disrupting the vegetation, or dirtying the water.

The bigger goldfish have an invasive nature and have become a natural threat to the native species in many lakes and ponds around the World. The government of many countries like Canada, the USA, and France has requested the fish owners not to release the goldfish into open freshwaters.

About the Author

Victoria Lamb

Victoria is a freshwater aquatics specialist, fish keeper, and amphibian enthusiast. She has had more than 6 years of experience caring for aquariums and keeping several fish species, and her home boasts of 3 aquariums and a garden pond. Her goal is to educate fish owners on raising healthy and happy aquatic pets.

Career Highlights:

  • Has worked with several aquarium manufacturers as a consultant
  • Organized and hosted workshops on freshwater fish keeping at retail stores, educational facilities, and libraries
  • Released content for the amphibian community through her writings

Educational Highlights:

Bachelor of Science in Animal Behavior and Welfare

  • University of Lincoln, Lincoln, UK (2014-2018)

Writing Experience

Victoria has done ghostwriting for many aquarium and pet websites in the past. She has also worked for Canada's largest natural health magazine- ALIVE, with 300,000 monthly circulations as a freelancer. She had six published articles on animal behavior and welfare during her graduation for her thesis.

View All Articles