Fancy Goldfish: The Nation's Favourite Pet Fish

01 November 2019

Of all the fish we keep as pets, none are as popular as Goldfish. Among these, the pedigree breeds referred to as fancy Goldfish generally get the most attention, and good quality specimens of these command the highest prices.

Across China and Japan wealthy businessmen will pay the equivalent of hundreds or even thousands of pounds for particularly fine specimens. This isn't merely conspicuous consumption but a traditional part of East Asian culture, Goldfish being seen as lucky animals that bring wealth, good health, and happiness to their keepers. In fact, in some countries, it is tradition for newly married men to give one to their wives on the first wedding anniversary.

A common misconception amongst the general public is that goldfish have short three-second memories. However, this is incorrect because they can actually remember things that happened up to three months ago and sometimes even more. In fact, Goldfish have a sense of routine and can actually be trained to do simple tricks like swimming through hoops or pulling a lever to release food.

Good quality specimens of the common varieties can be found in most aquarium shops, and for many aquarists these are a good way to get into this aspect of the hobby. But the best quality specimens are less frequently imported and consequently more expensive, especially the premium fish produced in Japan. On top of this, some varieties simply don't get exported that often, and only those retailers who specialise in coldwater fish or rarities, such as Wildwoods, are likely to have the best A grade versions in stock.

As with any pedigree pet, whether dog, cat, or fish, you tend to get what you pay for. This doesn't necessarily mean the less expensive fish are sickly, but rather their colouration, body shape, or fin lengths might not exactly match up to the standards set by the master breeders. Such specimens are among the most visually striking fish in the hobby though, and not difficult to maintain if a few basic rules are understood.

Tank size

Goldfish are not small fish, and the idea they can be kept in bowls or very small tanks is completely wrong. While some specimens may survive for a while in such environments, the reality is that most specimens kept in bowls end up dead within a few weeks or months. Because they are social animals, they are best kept in groups of three or more specimens, and that means a fairly large tank has to be provided. Most fancy varieties get to about 20 cm (8 inches) within 2-3 years, so an aquarium upwards of 135 litres (30 gallons) should be considered the absolute minimum. After the first three, allow at least another 45 litres (10 gallons) per additional specimen.

The shape of the tank is important. Deep tanks suit the fancy varieties with long fins and stocky bodies like Orandas. The extra depth allows them to swim easily without dragging their fins across the substrate. Longer tanks are best for the single-tailed varieties that are most active swimmers, such as Comets. Note that the single-tail varieties are also the species also suited to use in garden ponds, something that cannot be said for most of the double-tail varieties (at least in countries where ponds freeze over in winter).


Goldfish are messy feeders that tend to create a lot of silt by stirring up the bottom of the tank. Robust filtration is necessary not just to ensure good water quality but also water clarity. External or internal canisters are a good default choice, but turbulent water currents should be avoided where the slow-moving fancy varieties are being kept. Hang-on-the-back (HOB) filters are also popular choices, producing less turbulent water currents while being easier to maintain than external canister filters in particular.

Large sponge filters can work, and are ideally suited to use with the more extreme varieties, such as Bubble-eyes, that are easily damaged by strong currents. The main drawback to using a sponge filter is its limited ability to remove silt from the bottom of the tank, so some degree of spot cleaning using a small net or turkey baster may be necessary to ensure perfect water quality.

Some aquarists use undergravel filters for Goldfish, and these can work well if properly set up and maintained. They don't do a good job of removing silt though, since they work by sucking water, and any silt particles, into the gravel. Periodically stirring the gravel while siphoning out the muck that appears will help to keep the tank clean, and will probably need to be done every week or so for best results.

Water chemistry

Although Goldfish are adaptable, they prefer neutral to slightly basic, moderately hard water chemistry. In soft and acidic conditions they may be more prone to bacterial infections such as Finrot. Aim for around 10-20 degrees dH, pH 7-8. The use of Rift Valley salt mixes can be useful if you have very soft water, used at 50-100% the dose recommended for a typical Malawian or Tanganyikan set-up. Goldfish are reasonably tolerant of gradual changes in water chemistry, but sudden changes should be avoided, especially with the more delicate fancy forms. Acclimatise these carefully to their new home if the dealer maintained them at significantly different water chemistry parameters.

Water temperature

As mentioned above, the hardy single-tail varieties like Comets and Shubunkins will do as well outdoors as standard Goldfish. But otherwise fancy Goldfish appreciate what might be considered subtropical temperatures between 18-22 degrees C. In fact an unheated tank in a centrally-heated room is usually fine, but if you're keeping the more delicate twin-tailed varieties, a heater set to 20 degrees C will ensure they never get too cold, even in winter.


Goldfish are omnivores, and when kept in ponds eat substantial amounts of algae and decomposing plant material alongside whatever pellet foods they are offered. This generally ensures good health, but when Goldfish are kept in fish tanks, they are prone to constipation if they do not receive sufficient 'greens' in their diet. In extreme cases, constipation leads to the 'floaty, bloated' Goldfish unable to swim properly, even being stuck swimming upside down. Less severe cases of constipation reveal themselves through the stringy, thread-like faeces seen trailing from the vent.

Suitable green foods include cooked peas and spinach, but many aquarists simply leave bunches of inexpensive pondweed (such as Elodea) in the tank that the fish will graze on when hungry. Good quality flakes and pellets can also be used of course, including Koi pellets, but Goldfish are prone to over-eating these protein-rich foods if given to excess.


Since Goldfish will eat soft plants, it's easier to decorate their tank with smooth rocks and bogwood if you're going for a naturalistic aquarium. Some tropical plants can thrive in coldwater tanks though, including Vallisneria, but it's often safer to stick with artificial plants. Avoid using these with the more delicate fancy Goldfish, such as Orandas as these are likely to be scratched by the sharp edges on many plastic plants.


Goldfish are divided into two main types: single-tail and double-tail varieties. As a rule, the single-tail varieties are hardier and easier to keep, but some of the double-tail varieties are largely unproblematic if housed and maintained properly.

The Comet is one of the best-known single-tail varieties. Essentially a standard Goldfish with longer fins, it is very hardy and an excellent pond fish. Adults get quite big, 25-30 cm, and are notoriously active, even boisterous. Comets are unusual among fancy Goldfish in being a Western rather than Eastern variety, originating in the United States. Comets are widely sold and generally inexpensive, but expect to pay more for the best quality fish with deeply-forked and erect fins compared with the more droopy or uneven fins seen on the mass-produced specimens.

There are three different Shubunkins recognised in the hobby: American, London, and Bristol Shubunkins. All have shiny, pearly-white bodies with patches of black, orange, red and blue colouration. Bristol Shubunkins and American Shubunkins somewhat resemble Comets in shape and fins, though Americans have longer and more deeply-forked tail fins than those seen on Bristol Shubunkins. London Shubunkins are more stocky in body shape and have shorter fins, so are closer to standard Goldfish in appearance if not colouration. All the Shubunkins are hardy, easily maintained fish that mix well with other robust Goldfish varieties including Comets and standard Goldfish.

Among the double-tail varieties, Black Moors are among the most widely traded and easily kept. They are generally very hardy, but given their large adult size, over 20 cm, and boisterous personalities, they are not suitable for mixing with the more delicate fancy Goldfish. On the other hand, Black Moors mix well with single-tail Goldfish like Shubunkins, provided adequate swimming space is provided for all the fish being kept.

While often treated as a separate breed, Black Moors are really just the velvety-black colour form of the Telescope breed notable for its fan-like tail and protuberant eyes. The other colour forms are not quite as popular as the Black Moor, at least in the UK, but shouldn't be too difficult to obtain.

The Ryukin is named after the Ryukyu Islands where the breed originated. They have stocky bodies including a distinct hump over the pectoral fins that renders the fish almost as deep as it is long. Ryukins may look odd, but they are large and quite powerful fish that tend to be pushy at feeding time. So like Telescopes they're best kept with other robust varieties.

Although rarely seen in the UK, Dragon Eyes are highly regarded in China, where they originated. They are essentially Black Moors in shape, but with larger and more protuberant eyes. Some have extra colouration around the throat and flanks, and good quality specimens are very striking.

Veiltails are another widely seen double-tail variety. They lack the goggle-like eyes of Telescopes, but have a similarly stocky build and even longer fins. As their name suggests, their tail fin is flamboyant in its development, and while attractive, this does mean the fish struggles to swim quickly. Easily bullied, these fish are otherwise undemanding and do well if kept alongside the gentler varieties such as Orandas.

Among the more delicate double-tail varieties are the Orandas, of which numerous colour forms are recognised. They are characterised by a fleshy growth on their heads, called a 'wen' in Japanese. While not especially difficult to keep, Orandas are easily damaged by strong currents, sharp objects and aggressive tankmates. If the 'wen' is scratched it can quickly become infected, which will require antibacterial medication to fix. As ever though, prevention is better than cure!

Broadtail Orandas, also known as Orchid Orandas, are specimens with tail fins lacking the deep forks seen on standard Orandas. This results in fins resembling flower petals in shape, and when properly coloured, exotic flowers at that! Needless to say, the best quality specimens are not going to be cheap, but few fish rival them when it comes to exotic beauty.

The Lionhead is another fairly delicate variety. These have stocky bodies, slightly down-turned tails with relatively short fins, and no dorsal fin. Their name comes from the slight fleshy growth around the head resembling a lion's mane. While basically undemanding, their particular body shape makes them slow swimmers and unable to compete with the more boisterous varieties. Strong water currents will cause them problems too.

Two varieties that are popular in the Far East but rather 'marmite' in the UK are Celestials and Bubble-eyes. Celestials have eyes pointed upwards, making it impossible for them to see what's going on below them. In reality fish tend to use eyesight to a lesser degree than humans, using their lateral line system as a sort of 'distance touch' that works a lot better in murky water or at night. So while Celestials may be handicapped to some degree, and thus compete poorly with most other types of Goldfish, they are certainly not incapable of finding food and or navigating around the aquarium.

Like Celestials, Bubble-eyes are best kept among their own kind. They are somewhat similar to Lionheads in overall shape, but have large, fluid-filled sacs below their eyes that might look interesting but are very easily damaged by boisterous tankmates and sharp objects. Because they are more difficult to keep, neither Celestials nor Bubble-eyes have become regular sights in aquarium shops, but they do get imported occasionally and might well appeal to the more advanced aquarist able to cater to their specific needs. They are not to be recommended to casual aquarists though, and certainly can't be mixed with other types of Goldfish.

Wildwoods are able to deliver many different kinds of fancy goldfish via a specialist courier APC. All of which are of incredibly ideal quality. If you would like to know what is in stock, send us an email:

This article was written for Tropical Fish Finder by: Neale Monks, Palaeontologist and can not be reproduced without permission.