Musky Trout Hatcheries LLC.
279 Bloomsbury Road • Asbury, NJ 08802 • Warren County
ph: 908•479•4893    fax: 908•479•4855   •   musky279@yahoo.com

Koi

Koi are ornamental domesticated varieties of the common carp that originated from China and widely spread in Japan. They are very closely related to goldfish and, in fact, the style of breeding and ornamentation has become very similar, probably through the efforts of Japanese breeders to emulate goldfish. Koi and tattoos of koi are traditionally considered lucky.

The word "koi" comes from Japanese. The original Japanese word koi simply means "carp," including both the dull grey fish and the brightly colored varieties. A homonym of koi means 'love, affection' and koi are therefore symbols of love and friendship in Japan: a good example is the short story Koi-san by Mukoda Kuniko.

Koi varieties are distinguished by coloration, patterning, and scalation. Ghost koi, developed in the 1980s are metallic hybrids of wild carp and Ogon koi and are not considered true Nishikigoi. Butterfly Koi, Longfin koi, or Dragon Carp were also developed in the 1980s and are notable for their long and flowing fins. They are actually hybrids with Asian Carp and, like Ghost koi, are not considered true Nishikigoi.

Koi have many different colors. Some of the major colors are white, black, red, yellow, blue, and cream.
While possible variations are limitless, breeders have identified and named a number of specific categories. The most popular category is Gosanke. The Gosanke category is made up of the Kohaku, Taisho Sanshoku, and Showa Sanshoku varieties. The Japanese breeders have many generations of knowledge and experience when it comes to breeding and raising Nishikigoi. They know which ones will be worth a couple hundred dollars and which ones will be a couple hundred thousand dollars.

 

The major named varieties include:

 

Kohaku - a white-skinned Koi, with a red pattern
Taisho Sanshoku (Sanke) - a white-skinned Koi with a red and black pattern
Showa Sanshoku (Showa) - a black-skinned Koi with a red and white pattern
Tancho - Any koi with the only red being in a circle on its forehead. The fish can be a Tancho Showa, Tancho Sanke, or even Tancho Goshiki.
Asagi - a Koi with light blue scales on its top and red scales on its bottom
Shusui - the partially scaled version of an Asagi
Bekko - a white, red, or yellow-skinned Koi with a black pattern
Utsurimono - a black Koi with a red, white, or yellow pattern
Goshiki - a mostly black Koi with red, white, brown, and blue accents
Ogon - a Koi that is one solid color, can be regular or metallic; known colors - red, orange, platinum, yellow and cream
KinGinRin - Koi with shiny scales "Gold Silver Scales" There is also Gin rin versions of almost any other type of koi. For example, You could have a showa with glittery scales.
Kawarimono (kawarigoi) - Miscellaneous types of Koi
Doitsu-goi - German Carp
Koromo - Koi with areas of blue-edged scales (align neatly)
Hikari-Moyomono - Koi with coloured patterns over a metallic base, and koi in two metallic colours
Ghost koi - "Hybrid" of Ogon and wild carp. Not Nishikigoi.
Butterfly Koi - Long-finned version of all others. Not Nishikigoi.

Keeping koi:

The common carp is a hardy fish, and koi retain that durability. They can be kept in anything from small containers to large outdoor ponds or water gardens. The traditional indoor aquarium is less desirable than a round plastic tub. Koi are cold water fish, so it's advisable to have a meter or more of depth in areas of the world that become warm during the summer. In areas that get harsh winters, it is a good idea to have a pond that is a minimum of 4.5 feet deep so that it won't freeze solid. It is also a good idea to keep a space open with a bubbler and a horse trough heater.

Koi's bright colors put them at a severe disadvantage against predators; a white-skinned Kohaku is a visual dinner bell against the dark green of a pond. Herons, Kingfishers, Racoons, Cats, Foxes, and Badgers are all capable of emptying a pond of its fish. A well-designed outdoor pond will have areas too deep for herons to stand in, overhangs high enough above the water that mammals can't reach in, and shade trees overhead to block the view of aerial passersby. It may prove necessary to string nets or wires above the surface. The pond should include a pump and filtration system to keep the water clear.

Koi are bottom-feeders, so koi food is not only nutritionally balanced, but designed to float so as to encourage them to come to the surface. When they are eating, you can also check for parasites and ulcers. Koi will recognize the person feeding them and gather around at dinnertime. They can even be trained to take the food from one's hand.

In the winter their digestive system slows nearly to a halt, and they eat very little, perhaps no more than nibbles of algae from the bottom. Their appetite won't come back until the water warms up in the spring. When the temperature drops below 50 °F, feeding, particularly with protein, should be halted or the food can go rancid in their stomach causing sickness.

If kept properly, koi can live about 30–40 years. Some have reportedly lived up to 200 years.

 

Breeding Koi:

Like most fish, koi reproduce through spawning in which a female lays a vast number of eggs and one or more males fertilize them. Nurturing the resulting offspring (referred to as fry) is a tricky and tedious job, usually done only by professionals. Although a koi breeder may carefully select the parents they wish based on their desired characteristics, the resulting fry will nonetheless exhibit a wide range of color and quality.

Unlike a purebred dog or cat, even the finest champion-grade koi will produce literally thousands of unacceptable, unrecognizable, or even genetically defective offspring in a single spawning. These (and hundreds of marginal offspring) are culled at various stages based on the breeder's expert eye and closely guarded techniques known to a rare few outside Japan.

Culled fry are usually destroyed (perhaps fed to other fish) and older culls are often sold as lower-grade "pond-quality" koi within their first year (also called "Tosai") at 3"–6" long. The semi-randomized result of the koi's reproductive process is both a blessing and a curse. While it requires diligent oversight to narrow down the favorable result that the breeder wanted all along, it also made possible the gradual transformation of wild river carp into the exquisite art form that we see in modern nishikigoi.

In the wild

Koi have been accidentally or deliberately released into the wild in every continent except Antartica. They greatly increase the turbidity of the water because they are constantly stirring up the substrate. This makes waterways unattractive, reduces the abundance of aquatic plants, and can render the water unsuitable for swimming or drinking even by livestock. In some countries, koi have caused so much damage to waterways that vast amounts of money and effort have been spent trying to eradicate them, largely unsuccessfully. Because of the danger to the environment koi possession is illegal in the state of Maine.

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The goldfish was one of the earliest fish to be domesticated, and is still one of the most commonly kept aquarium fish. A relatively small member of the carp family, the goldfish is a domesticated version of a dark-gray/brown carp native to east Asia (first domesticated in China) that was introduced to Europein the late 17th century. The mutation that gave rise to the goldfish is also known from other cyprinid species, such as common carp.

Goldfish may grow to a maximum length of 23 inches and a maximum weight of 9.9 pounds, although this is rare; few goldfish reach even half this size. In optimal conditions, goldfish may live more than 20 years (the world record is 49 years), but most household goldfish generally live only six to eight years, due to their often being kept in bowls.

 

History:
During the Tang Dynasty, it was popular to raise carp in ponds. As the result of a dominant genetic mutation, one of these carp displayed "gold" (actually yellowish orange) rather than silver coloration. People began to breed the gold variety instead of the silver variety, and began to display them in small containers. The fish were not kept in the containers permanently, but would be kept in a larger body of water, such as a pond, and only for special occasions at which guests were expected would they be moved to the smaller container.

 

Goldfish in ponds:

Goldfish are popular pond fish, since they are small, inexpensive, colourful, and very hardy. In a pond, they may even survive if brief periods of ice form on the surface, as long as there is enough oxygen remaining in the water and the pond does not freeze solid.

Common goldfish, London and Bristol shubunkins, jikin, wakin, comet and sometimes fantail can be kept in a pond all year round in temperate and subtropical climates. Moor, veiltail, oranda and lionhead are only safe in the summer.

Small to large ponds are fine though the depth should be at least 80 cm (30 in) to avoid freezing. During winter, goldfish will become sluggish, stop eating, and often stay on the bottom of the tank. This is completely normal; they will become active again in the spring. A filter is important to clear waste and keep the pond clean. Plants are essential as they act as part of the filtration system, as well as a food source for the fish. Plants are furthermore beneficial since they raise oxygen levels in the water.
Compatible fish include Koi, Comets, Shubunkins, but the latter will require specialized care. Ramshorn Snails are helpful by eating any algae that grows in the pond. It is of great importance to introduce fish that will consume excess goldfish eggs in the pond, such as orfe. Without some form of population control, goldfish ponds can easily become overstocked. Koi may also interbreed to produce a sterile new fish.

 

Feeding:

Like most fish, goldfish are opportunistic feeders. When an excess of food is offered, they will produce more waste and feces, partly due to incomplete digestion of protein. Overfed fish can sometimes be recognized by feces trailing from their cloaca. Goldfish need only be fed as much food as they can consume in one to two minutes, and no more than twice a day. Extreme overfeeding can be fatal, typically by bursting of the intestines. This happens most often with selectively bred goldfish, which have a convoluted intestinal tract as opposed to a straight one in common goldfish. Novice fishkeepers who have newly purchased ryukin, fantail, oranda, lionhead or other "fancy" goldfish will need to watch their fish carefully for a few days, as it is important to know how much the goldfish will eat in a couple minutes of time. Special goldfish food has a lower protein and higher carbohydrate content.

 

Behavior:

Behavior can vary widely both because goldfish are housed in a variety of environments, and because their behavior can be conditioned by their owners. Scientific studies done on the matter have shown that goldfish have strong associative learning abilities, as well as social learning skills. In addition, their strong visual acuity allows them to distinguish between different humans. It is quite possible that owners will notice the fish react favorably to them (swimming to the front of the glass, swimming rapidly around the tank, and going to the surface mouthing for food) while hiding when other people approach the tank. Over time, goldfish should learn to associate their owners and other humans with food, often "begging" for food whenever their owners approach. Auditory responses from a blind goldfish proved that he recognised one particular family member and a friend by voice, or vibration of sound. During feeding time the blind fish would wait for the food to fall rather than go to the top to feed among the many fish in the aquarium. This behavior was very remarkable because it showed that he recognised the vocal vibration or sound of two people specifically out of seven in the house, and wanted affection.

Goldfish also display a range of social behaviors. When new fish are introduced to the tank, aggressive social behaviors may sometimes be seen, such as chasing the new fish, or fin nipping. These usually stop within a few days. Fish that have been living together are often seen displaying schooling behavior, as well as displaying the same types of feeding behaviors. Goldfish may display similar behaviors when responding to their reflections in a mirror. Goldfish that have constant visual contact with humans also seem to stop associating them as a threat. After being kept in a tank for several weeks, it becomes possible to feed a goldfish by hand without it reacting in a frightened manner. Goldfish have behaviors, both as groups and as individuals that stem from native carp behavior.

 

Native environment:

Goldfish natively live in ponds, and other slow or still moving bodies of water in depths up to 65 ft. Their native climate is subtropical to tropical and they live in freshwater with a pH of 6.0–8.0, a water hardness of 5.0–19.0 dGH, and a temperature range of 40 to 106 °F although they will not survive long at the higher temperatures. They are considered ill-suited even to live in a heated tropical fish tank, as they are used to the greater amount of oxygen in unheated tanks, and some believe that the heat burns them. However, goldfish have been observed living for centuries in outdoor ponds in which the temperature often spikes above 86 °F. When found in nature, the goldfish are actually an olive green color.

While it is true that goldfish can survive in a fairly wide temperature range, the optimal range for indoor fish is 68 to 75 °F (20 to 23 °C). Pet goldfish, as with many other fish, will usually eat more food than it needs if given, which can lead to fatal intestinal blockage. They are omnivorous and do best with a wide variety of fresh vegetables and fruit to supplement a flake or pellet diet staple.

Sudden changes in water temperature can be fatal to any fish, including the goldfish. When transferring goldfish to a pond or a tank, the temperature in the storage container should be equalized by adding the destination water into the bag slowly (about 20 oz at a time for a few minutes) before releasing the goldfish. In addition, some temperature changes might simply be too great for even the hardy goldfish to adjust to. For example, buying a goldfish in a store, where the water might be 70 °F, and hoping to release it into your garden pond at 40 °F will probably result in the death of the goldfish, even if you use the slow immersion method just described. A goldfish will need a lot more time, perhaps days or weeks, to adjust to such a different temperature.

 

Breeding:

Goldfish lay eggs. They produce adhesive eggs that attach to aquatic vegetation. The eggs hatch within 48 to 72 hours, releasing fry large enough to be described as appearing like "an eyelash with two eyeballs". Within a week or so, the fry begin to look more like a goldfish in shape, although it can take as much as a year before they develop a mature goldfish color; until then they are a metallic brown like their wild ancestors. In their first weeks of existence, the fry grow remarkably fast - an adaptation born of the high risk of getting devoured by the adult goldfish (or other fish and insects) in their environment.

Goldfish can only grow to sexual maturity if given enough water and the right nutrition. However if kept well, they may breed indoors. Breeding usually happens after a significant change in temperature, often in spring. Eggs should then be separated into another tank, as the parents will likely eat any of their young that they happen upon. Dense plants such as Cabomba or Elodea or a spawning mop are used to catch the eggs.

Most goldfish can and will breed if left to themselves, particularly in pond settings. Males chase the females around, bumping and nudging them in order to prompt the females to release her eggs, which the males then fertilize. Due to the strange shapes of some extreme modern bred goldfish, certain types can no longer breed among themselves. In these cases, a method of artificial breeding is used called "hand stripping". This method keeps the breed going, but can be dangerous and harmful to the fish if not done correctly.

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A shubunkin is a type of single-tail goldfish with orange, white, black, red, and blue markings, blue being the most desired. Their body shape is like that of the common comet goldfish, Carassius auratus, of which they are a subspecies. Also called speckled goldfish, harlequin goldfish, calico goldfish, and coronation fish, they were developed in Japan about a hundred years ago by crossing calico fantails with comet goldfish to produce a hardy, able swimmer with bright colors.

There are three main types of shubunkin, the Bristol, which has a very large tail with rounded lobes, the London, which has a short rounded lobes, and the Japanese/American, which has a "normal" comet goldfish tail: deeply forked with long narrow lobes. They are a bit smaller than common comets, growing up to about 15 cm long. Like other goldfish, they are social, omnivorous, and can thrive in temperatures down to freezing.

An extremely hardy fish, which along with the common Goldfish, Comet, and fantail goldfish are ideally suited to beginners.

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WE ALSO OFFER TADPOLES WHEN AVAILABLE

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