When I was young, I never thought goldfish could grow over 3 inches. After all, nothing is more emblematic in the world of fish keeping than a cute and tiny goldfish swimming in a small fishbowl.
Every time someone thinks of fish, an image of a tiny goldie in a bowl usually comes into mind.
But, every experienced aquarist knows that the ubiquitous bowls are inappropriate for the enjoyment, health as well as display value of your marvelous and eye-catching goldfish.
And, every fish keepers know that a goldfish can grow more than 3 inches with the appropriate living conditions and nutrition.
So, how big can a goldfish get? Want to know the techniques and ways to increase the size of your goldfish?
Guess what?
As you read this blog post, you will definitely discover a plethora of valuable tips and hacks that will help you keep a healthy and happy goldfish.
Contents
How Big are the World’s Largest Goldfish?
One of the largest goldfish in the world was from Kent, England. The goldfish was named by its owners as “Goldie”.
And, in its 15 years of existence, Goldie grew over 15 inches long and 5 inches tall. For comparison purposes, Goldie is almost 3 times bigger than the average domesticated goldfish.
And, did I mention that it weighed over a couple of pounds?
Although Goldie lived in a relatively small aquarium, it still had a happy and healthy life, thanks to the owner’s excellent care.
The world’s longest goldfish, according to Guinness World Records, measured 18.7 inches from tail-fin end to snout.
And, there are plenty of other gigantic goldfish discovered. In Danville, Kentucky, a man snagged a humongous 20-pound goldfish.
Since goldfish are part of the well-known carp family, these fish can grow pretty big, depending on their genetics and environment.
Check out this fantastic video!
How Big Can a Goldfish Get in an Aquarium?
It depends on the breed and kind of goldfish you have in your aquarium. But, an adult domesticated goldfish, on average, weighs around 8 ounces and is 2 to 5 inches long.
Fancy goldfish varieties, which are slimmer and longer, may weigh up to 12 ounces.
But the thing is, goldfish can be a little bigger than these sizes.
Take note that goldfish continuously grow throughout their life. And, sometimes, it has an unsuitable aquatic environment that stunts their growth.
A small aquarium, for instance, cannot provide the amount of oxygen that your goldfish needs. And, a poor filtration system can also stunt their growth since it contaminates the aquarium water pretty quickly.
With proper care and maintenance, a domestic goldfish can grow up to 12 inches. Keep in mind that “Goldie” was also a domesticated goldfish that grew up to 15 inches long.
Who knows? With proper care, your goldfish might be the next world record holder.
How Big Can a Goldfish Get in the Wild?
In the wild, goldfish grow so much bigger than the domesticated ones kept in aquariums. As a matter of fact, goldfish living in the wild can grow around 12 to 14 inches and may weigh about 3 pounds.
But, why do they grow incredibly big in a non-aquarium setting? Well, thing is, there are a few reasons why goldfish thrive in the wild.
For one, their ecosystem and environment are incredibly different. They have a sufficient supply of oxygen, and have plenty of natural filtration and water available, meaning their water will not be contaminated.
And, unlike cats, dogs, and other typical pets, goldfish do not stop growing until they die. Sure, they do not grow at a predictable and steady rate, but they still grow in bursts.
And, they will have tons of opportunities to grow in the wild where oxygen and food are practically unlimited.
Can I Release My Goldfish in the Wild?
Even with the outstanding growth rate, you should never release your goldfish in the wild. Goldfish are, in essence, a domesticated variety of an eastern Asian native carp, meaning they do not look natural in the wild.
If you catch or see a genuine goldfish in a lake or pond, such an aquarium pet was likely released by its owner in the wild because it was getting too big.
It is, however, not a bright idea and is even illegal in some places because goldfish released in the wild can cause a myriad of issues for the native fish species.
Goldfish are an invasive species that may take over the whole population of natural fish when released in the wild.
So, if you have goldfish that is getting too big for your aquarium, the best solution is to set up a new and larger tank.
Alternatively, you may have it adopted by someone more capable of handling a bigger goldfish.
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Factors That Affect the Size and Growth of Goldfish
Several factors affect the growth of your pet goldfish. Here are some vital things that you should take note of as you keep a goldfish in your aquarium.
Genetics
No matter what you do, some fish just do not grow. You may feed them with the best goldfish available, provide the most innovative aquarium equipment, and create an extra spacious tank for them.
And, yet, they still remain tiny because of their genetics.
Call them midgets, runts, or whatever you want.
There is certainly nothing you or any owner can do to reverse it.
You do not have to panic, though. The size of your goldfish will not affect its duration or quality of life.
And, it can be an upside for pet owners who want to save money and space on their aquarium.
The Number of Fish in the Aquarium
The more fish mates in your aquarium, the harder it is for them to grow. In a community tank, goldfish will have to compete for food, space, and attention, While it is not as crucial as genetics, it can have a little impact on the growth of your goldfish.
Also, if you want them big, opt for common goldfish. They are the largest goldfish species, capable of reaching a whopping length of 18 inches. With proper care, they can even weigh up to 10 pounds.
Quality of Their Environment
Goldfish will not grow when they are kept in a low-quality aquatic environment. Moreover, they may develop diseases as well as physical deformities.
Maintaining high-quality aquarium water does not guarantee that your goldfish will grow. Even so, it will give them a higher chance of getting bigger. Plus, it will improve their overall health and make them happy.
How to Make Your Fish Grow Bigger?
There are several ways to help your goldfish grow big and healthy. And, I am going to reveal some of the best methods and techniques to help your goldfish grow and live a happy life.
Look for Goldfish with Exceptional Genes
All in all, the growth of your goldfish all comes down to one thing: genetics.
There is nothing you can do if your fish do not have the best genetics.
Even the best goldfish food will not make any impact on your fish’s growth.
If the parents and ancestors of your goldfish did not reach an ideal size, it is likely your pet will not grow as big as you want it to be.
So, look for a genetically-blessed goldfish from reputable and passionate breeders rather than buying them from chain pet stores.
Set an Ideal Water Temperature
According to recent scientific studies, the water temperature can significantly affect the growth rate of your goldfish.
The ideal temperature, for optimum growth of your goldfish, is between 71 and 75 °F.
Even though these fish can survive in cold water temperatures of around 65 °F, it is not exactly an ideal setting for goldfish growth.
The truth is, the fish’s body functions and metabolism slow down in colder temperatures. This, in turn, will stunt their growth.
As a matter of fact, “Goldie”, the giant goldfish, grew extremely large because it had the ideal water temperatures. Truthfully, Goldie did not even have a big and roomy aquatic environment.
Proper Nutrition
Proper nutrition is crucial to your goldfish’s growth, especially in the first year of their life. And, at this stage of their life, it is essential to give them high and healthy amounts of protein.
If you want your goldfish to grow pretty big, you have to give them a high protein diet.
Protein basically stimulates growth, and they must get plenty of it while they are young.
And, the protein will remain a vital part of their diet as they age.
But, you also have to make sure that they consume a wide array of other nutrients. And do not forget to give them some live food and vegetables.
When it comes to feeding a goldfish, you should focus on quality and not on quantity.
The truth is, feeding them too much can cause some severe health problems for your goldfish.
To improve your goldfish’s growth rate, you might want to make any of these options as your pet’s staple diet:
- Aqueon food granules
- API Goldfish food
- Hikari USA fish food
- Tetrafin food flakes for goldfish
- Laguna All Season
- Repashy gel fish food
- Omega One food for goldfish
- Tetrapond food sticks
- New Life Spectrum food for goldfish
- Wardley Pond food pellets
Additionally, you may feed these things to your goldfish to help them grow big:
- Algae wafers
- Bloodworms
- Algae
- Live aquatic plants
- Brine shrimp
- Daphnia
- Fruits
- Green, leafy vegetables
- Fish food (homemade)
- Insects
- Mosquito larvae
- Live food (small)
- Squid
- Worms
Avoid Fish Bowls
Fishbowls are an absolute no-no in fishkeeping. Not only are they rather small, but these bowls also limit the oxygen amount that a goldfish needs to thrive and survive.
Keep in mind that the top opening of a fishbowl is smaller than its largest radius.
Furthermore, they are not designed to accommodate air pumps, filtration systems, and other handy fish keeping equipment.
Truth be told, your goldfish will not reach its adolescent stage if you put it in a fishbowl.
FAQs
What is the Lifespan of a Goldfish?
Contrary to popular belief, goldfish have a rather long lifespan. Actually, they are among the longest living pet fish to date.
One goldfish even lived up to 49 years.
Most goldfish die young because they are not kept in their ideal conditions.
With proper care, a single tail goldfish can live around 20 years. A fancy goldfish, meanwhile, has a life expectancy of 12 years.
What is the Ideal Aquarium Size for a Goldfish?
For the common goldfish, your aquarium should have a capacity of at least 48 gallons for the first fish. Then, it should have an extra 14 gallons for every extra goldfish.
The aquarium must have a minimum length of 120 centimeters (4 feet) to allow plenty of swimming room.
Single tail goldfish are more suitable for a pond setting.
As for the fancy goldfish, a 30-gallon capacity is recommended for the first fish. Afterward, you should add 12 gallons for every extra goldfish.
The aquarium for your goldfish should be at least 3 feet long, to provide ample swimming room. Moreover, it is highly recommended to use an external filter.
Are Koi and Goldfish the Same Fish?
Koi and goldfish are closely related and belong to the same fish family: Cyprinidae. But they are not the same. Goldfish are the domesticated ornamental descendants of the Carassius carassius (crucian carp). At the same time, the koi are bred selectively from the common carp.
Do Goldfish Have 3-second Memories?
There is absolutely no truth to this theory. A goldfish can sometimes remember moments and experiences up to 3 months ago. And, since they have a sense of routine, goldfish can even be trained to do a few small tricks, such as pulling levers to release their food as well as swimming through hoops.