How long do Goldfish live?
This is a frequently asked question because some Goldfish keepers manage to keep their Goldfish for years, sometimes decades, yet others only manage to keep them for a few months.
10 years should be considered a minimum for a well cared for Goldfish. 20+ years is not uncommon for pond fish, and there are records of Goldfish living for over 40 years.
A common misconception is Goldfish are small fish that have a similar lifespan to a small to medium sized tropical fish, 2-4 years at best. This is a reasonable assumption because depending on your own personal experience, you may have had Goldfish live for only a few months or years.
Guppies are breeding at 6 weeks old. Goldfish only start to show what sex they are at around 6 months at the earliest, and wouldn't breed until the following spring.
What all this indicates is Goldfish are going to live a lot longer than the average tropical fish.
Common Goldfish kept in ideal conditions can grow to 12 inches (300mm) in body length, and possibly even larger in the wild. This is a large aquarium fish by any standards, and generally, the larger the animal, the longer it lives. But size isn’t the only factor that determines how long a Goldfish will live.
Many factors determine how long any living creature will live for and Goldfish are no different.
Here are the most important ones:
Water quality is the most frequent cause of premature death in Goldfish.
Goldfish will tolerate a wide variety of water conditions, but this does not include polluted water which has ammonia or nitrites present. Both damage skin and gills and nitrites stop the uptake of oxygen. If they don’t kill the fish directly, they will cause stress which will shorten its lifespan.
Nitrates, although far less toxic than nitrites, still have a detrimental affect on Goldfish if they rise too high. Where once it was believed nitrates as high as 200ppm (parts per million) were safe, now anything over 40ppm is considered getting into the dangerous level.
High nitrates constrict the blood vessels, and this can lead to buoyancy problems in fancy varieties as the blood vessels surrounding the swim bladders have reduced ability to supply oxygen.
I have found young fry (babies), will start showing buoyancy problems when nitrates rise above 5ppm.
Ideal water conditions for Goldfish are:
The natural foods of Goldfish are aquatic plants, invertebrates, insect larvae, daphnia and any other animals they can fit into their mouths.
All these foods are soft, moist and easily ingested. The majority of commercially available foods for Goldfish are dry prepared flakes or pellets.
The rear air or swim bladder of a Goldfish has an opening into the digestive tract. The Goldfish controls its buoyancy by inflating or deflating its swim bladder by gulping or expelling air through its mouth.
If poor quality or stale food is eaten, it can cause two problems, constipation or gas build-up in the intestine.
Both these conditions stop the Goldfish’s ability to control its buoyancy, which is why after being fed dry prepared food, Goldfish often develop buoyancy problems until the food passes through the intestine.
This isn’t such a problem with slim bodied varieties such as Comets, but as deep bodied fancy varieties get older, they become less tolerant of dry prepared foods and a lack of green matter in their diet. If they don’t get a change of diet this condition often turns permanent, and due to other complications, the fish usually die soon after.
I have a strain of Black Moor that as they age they start to get
buoyancy issues, especially if fed flake food or pellets. Since
changing to gel foods several years ago, I haven't had a single fish die from complications from a swim bladder disorder. Occasionally I still get a fish that gets a buoyancy problem, but it is usually temporary, and I know it's not caused by diet.
For those who keep or have kept small tropical fish will have found most lifespans are fairly short, 5 years being exceptional. One of the reasons for this is the high water temperatures they live in all year round, and with that comes a high metabolic rate. Water temperature plays a large part in the lifespan of fish. The colder the water the longer they live.
Goldfish are warm water fish, not tropical. They can live in water just above freezing and will survive at temperatures as high as 38oC (100oF) but prefer temperatures around the low 20s Celsius (68-74oF).
Most Goldfish live in unheated aquariums and ponds, so when winter arrives with its lower temperatures, Goldfish go into a period of low activity or if temperatures are low enough, hibernation.
Goldfish owners that keep their fish heated at higher temperatures all year round are dramatically shortening the lives of their fish!
Having said that, I don’t let my fancy varieties stay in water below 10oC (50oF) for any length of time, and my water never freezes.
Size seems to have a bearing on lifespan. For a Goldfish to reach its maximum size, it needs a lot of space. This is why the largest specimens seen are usually fish caught in natural waterways.
Fish kept in aquariums and bowls rarely have pristine water conditions. Goldfish release growth inhibiting pheromones, and unless their water is changed very frequently, their growth is always being affected by these pheromones. Aquarium raised fish seldom reach the size of pond raised fish.
Generally, fish kept in ponds live the longest, fish kept in bowls the shortest. Aquarium fish moved to ponds over the warmer months seem to get a health boost. Exposure to sunlight, natural foods, and a growth spurt are probably factors.
Fry (baby goldfish) are susceptible to parasites, especially flukes. If they get infested, they either die or their growth rate is severely slowed.
The first few weeks are when the most growth takes place. If fry are stunted because of parasites or poor water conditions they never recover from this. They always remain undersized compared to similarly aged fish, and don’t seem so robust.
I take meticulous care to ensure eggs and fry are not exposed to any parasites the adults may be carrying by flushing the eggs with fresh clean water and transferring them to a hatching tank. I also treat the adults for parasites at the start of the breeding season, even though I know they most likely aren't carrying any.
The health of a Goldfish is largely governed by water quality, but all the previously mentioned factors have a bearing on overall health.
If a fish is carrying parasites such as lice or anchor worm, which occurs irrespective of water quality, it will be weakened by the parasites and is susceptible to secondary diseases such as bacterial infection and fungus, both fatal if left untreated.
This is one of the most common mistakes novice Goldfish keepers make.
They are expecting a myopic (short-sighted), slow swimming fish to compete with normal eyed, fast and agile single tailed varieties.
What generally happens is over time the highly developed variety slowly starves, until finally it succumbs to a disease. This helps perpetuate the myth that fancy varieties don’t live very long.
Competition for food is so fierce that when I keep Celestials and Black Moor together temporarily, I notice the Celestials soon start to lose condition.
There are over 100 different varieties of Goldfish. The more developed varieties such as Celestials, Water Bubble Eyes and Moors have the most mutated genes, and this is believed to make them weaker.
Having said that, I have seen pictures of a 40+ year old Oranda.
Inbreeding has the same weakening effect, which is why some top breeders cross their fancy varieties back to Common Goldfish after a certain number of successive years of line breeding to re-strengthen the gene pool.
The rate an animal ages is built into its genetic blueprint at birth. However, most Goldfish never live long enough for it to be considered a cause of death. Most Goldfish only live at best, around 20% of their potential lifespan
So, the question should not be how long do Goldfish live? but, how long should Goldfish live?.
Goldfish are revered in China and Japan and have been kept there for centuries, so they should know how to look after them. In these countries, there have been recorded instances where Goldfish have attained the ripe old age of 40+ years.
This isn't common, but 20-30 years old is.
For fish kept in a bowl, 3 years would be an exceptional lifespan.
In an aquarium, with filtration, 10 years should be expected, longer if they spend some time each year outside in a pond.
In a pond with filtration, 15+ years isn't uncommon.
Goldfish that have lived long lives in aquariums seem to have these characteristics:
There is some evidence that Asian sourced fish are not long-lived fish, with 5 years being a maximum age.
These fish are kept in very warm water to speed up growth, and are fed continuously on high carbohydrate foods to promote deep bodies. Some of these fish attain almost full size within 12 months.
Large fish are popular and sell at high prices.
Breeders find these forced-grown fish hard to breed with spawn sizes small. Fish that experience winter temperatures after the growing season, as happens in the wild, appear to be more robust and are bred more successfully.
A lot of the factors that affect how long a Goldfish will live are pre-determined before you even see the fish in your favorite local fish store, but the most important ones you can influence are:
Goldfish kept in bowls have the shortest lifespans. Those kept in ponds have the longest. Always maintain high water quality through frequent water changes. Use a water test kit to measure your aquarium or pond water pH, nitrate and ammonia levels. As soon as one of these moves outside the desired range, make a water change.
Unless you change the water in a bowl daily, it is very hard to keep the water quality high.
Aquariums make it much easier to manage water quality using filters, but water changes still aren't done often enough.
Ponds allow Goldfish to grow large and receive natural sunlight. If Goldfish are put into a pond over the warmer months it seems to give their coloration and health a boost.
Feed live foods and vegetable matter as often as possible, and when these aren’t available, high-quality foods that copy the natural foods of Goldfish, namely soft, moist and easily digestible. Gel foods fit these requirements exactly.
Quarantining New Arrivals
Introducing a few fish into your fish community without first quarantining it is like playing a lottery. You may be very lucky and have no problems whatsoever, or, you will spend the next few months medicating all your fish.
Quarantining should include treating the new fish for parasites whether it is displaying symptoms of them or not. Healthy fish can carry a few parasites without ever succumbing to them, and your fish may not have had much exposure to ones the new fish could by carrying.
Likewise, you need to be sure your existing fish aren’t carrying any parasites that the new fish may not have been exposed to. Often a healthy, disease free post-quarantined fish will start to develop disease symptoms a few days after being put into a community tank .