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Koi fish are colored carp that live in man made ponds. Keeping them as pets is can be fun and relaxing hobby.


the contents of this article is Courtesy to : Koi Fish - Beginner Guide

Contents : 


  • Koi History

  • The Koi Keeping Hobby

  • Your Koi’s Home

  • Growing Your Collection

  • Basic Care

  • Sources

  • Further Reading

Koi History :


In Niigata, Japan, the large amount of snowfall each winter would often leave the rice farmers that lived in the mountainous region isolated for extended periods of time. They needed a source of protein during the winter season, so they would keep carp (Magoi) in a trench or unused rice paddy (the carp would have decimated the rice crop). In the fall, they would harvest and salt most of the carp fingerlings, leaving out a few to breed in the spring to replenish their stocks.


The carp were also very beneficial to the rice crop. When water was used to replenish the rice paddies, the carp waste in it made an excellent fertilizer.


Some of the carp they kept had patches of red color. We know that around the beginning of the 19th century at least one of the rice farmers took notice of this and in their spare time, began to selectively breed these unique carp in an attempt to bring out their color .


Over the years, the Koi keeping hobby spread across Japan. Most of the people that kept Koi were well to do businessmen. The Koi were transported in wooden buckets by the breeders, who would take them from from their farm to the hobbyist’s home. There were no oxygen tanks or aerators, so the survival rate was mediocre.


Koi keeping stayed in Japan until the early 1960’s, when polypropylene bags and jet travel allowed for quick and safe transportation all over the world.

The Koi Keeping Hobby: 


Advanced collectors often join a local Koi club. Koi clubs are a great resource for Koi keeping information. Hobbyists meet about once a month to share Koi care tips and any new updates for the hobby.


ome clubs host an annual Koi show. Members take their Koi from their ponds and place them into tanks to enter their fish in the show. The Koi are separated by type and size and then are judged on body conformation and color. There are winners for each type and size category, but there is only one grand champion. The owner of the grand champion receives a trophy and gets the bragging rights until the next annual Koi show.




Your Koi’s Home :


Koi keepers often obsess over water quality and filtration. Koi take care of themselves (just add food) but the majority ponds that house the fish are too small to be self sustaining. They require a filter system to remove the fish waste from the pond water before it harms the Koi. A good filter system will incorporate different stages of filtration to efficiently remove each type of waste from the pond.


Koi thrive in a stable environment. Large temperature fluctuations can easily happen in a shallow pond, so the pond itself should be at least 3 feet deep. The pond should also have steep edges that will deter predators like herons or raccoons from wading into it.

Where to Find Koi :


Always quarantine any fish before adding it to your pond.  


There are many places that sell Koi fish. You can find them in big box retailers, mom & pop pet stores, nursery & landscaping centers, domestic Koi farms and specialty Koi shops. Big box retailers and nursery & landscape centers usually carry low grade (color) Koi in questionable tank systems. Due to the conditions the fish are kept in these places, survival rates aren't the greatest.


Pet stores and domestic Koi farms usually carry medium grade Koi fish. Koi are kept in excellent tank conditions due to the knowledgeable staff.


Specialty Koi shops usually carry medium and high grade Koi. The fish are kept in pristine conditions since the Koi that are imported are very expensive. Pond supplies and filtration equipment is often also sold at specialty Koi shops.




























Basic Care: 



Like we stated before, Koi take care of themselves for the most part, but it is up to you to keep their pond clean and to provide the with adequate nourishment. The amount of cleaning you do is dependant on how good your filter system is. An efficient filter system will require minimal maintenance whereas a cheap and poorly designed system will require a ton of work to keep it running.


Koi are usually fed twice a day. Only give them an amount of food that they can eat within 5 minutes. They may spend most of their day begging for good, but don’t overfeed, since it can lead to poor water quality and obesity problems. Koi have different feeding requirements for each season. 


Koi should be minimally handled. Netting them too often stresses them out. If the fish are stressed out, their immune system becomes suppressed, making them more susceptible to bacterial infections.


Sources : 


-Balon, Eugene K. "The common carp, Cyprinus carpio: its wild origin, domestication in aquaculture, and selection as colored nishikigoi." (1995).

-Takeda, Kaz “History of Niigata Nishikigoi”

-Axelrod, Herbert R. “The Completely Illustrated Guide to Koi for Your Pond” TFH, (1996).


Koi Health - Disease and Health Issues :


Koi can get sick. This is a fact that most beginning hobbyists learn the hard way. As the saying goes, an ounce of prevention is equal to a pound of cure. With Koi, the whole idea behind keeping this type of fish is their beauty. The best way to ruin a Koi's beauty is by getting a parasite or bacterial infection that can leave a scar for life. The #1 best way to keep a Koi beautiful and healthy is good water quality. Good water quality can be obtained by having a good filter system. These pages contain information on all of the most common diseases and ailments that can harm a Koi.


What can I do for my sick Koi?


Use the following tips to speed up recovery time if your Koi has an ulcer or bacterial infection.


1-Move the Koi to a hospital tank
Keeping Koi in a small tank during an illness will allow you to easily keep an eye on the fish during its treatment and recovery.  It will also let you easily catch the sick fish to administer treatment.  A hospital tank setup needs adequate filtration, aeration and regular water changes.  You want to provide an optimum environment for the Koi to live in while it's healing.


2-Add salt to the water
Add  one pound per 100 gallons of pure salt (no additives like Iodine) to boost their slime coat thickness and to help the sick Koi with its osmoregulatory system.  The osmoregulatory system controls how much water a fish absorbs and expels from its body.  If your Koi is in the pond, remove any plants.  Salt kills freshwater plants.


3-Follow the veterinarian's treatment regimenOnly a vet can prescribe internal antibiotics to an animal.  The vet will give you a treatment regimen to follow with the antibiotics.  If there are no fish vets in your area, you can try a Tricide-neo medicated bath to treat an ulcer.


4-Keep the water warm
Keep the water at 75 degrees F.  Warmer water speeds up their immune system and their healing time.


5-Don't move your Koi until it's healed upMoving your Koi back to the pond before the ulcer has healed is a bad idea.  The hospital tank will have a low bacteria count in the water, which is good for a healing Koi.  A pond will have a higher bacteria count, since it is a larger body of water that is stocked with many fish.  Moving your Koi back before it is healed up is a great way to have another infection happen to your fish.


koi diseases:


Click on the name for more information .. 


Parasites : 

Visible to the Naked Eye:


-Argulus (Fish Louse)

-Lernea (Anchor Worm)

-Ichthyophthirius multifilis (Ich, White Spot)


Not Visible to the Naked Eye:



-Gyrodactylus & Dactylogyrus (Skin and Gill Flukes)

-Ichthyobodo Necatrix (Costia)







Viruses : 


-Carp Gill Necrosis Virus (CGNV)

-Spring Viremia of Carp (SVC)

Koi Keeping Basics : 


Courtesy to 


If you are only going to read 1 page on this website, this just might be the one.Here we outline the common misconceptions and mistakes we see clients make that frankly are easily avoidable with just a little knowledge and common sense. Unfortunately, we even sometimes find that experienced pond keepers are making some basic mistakes that will hinder the performance of their ponds and potential hurt their fish


- Pond Stability: Fish Require Slow Changes


Changes should happen slowly in your pond. The key word is "stability". In nature, fish are accustomed to a gradually changing environment. While air temperature can change dramatically in a single day, your local lakes water temp will barely budge. The high specific heat capacity just won't allow this type of fluctuation. Water chemistryalso has a a continuity that the fish are accustomed too. The bottom line is, if you are to be successful, you need to provide a stable environment with a regular routine that is not stressful to its inhabitants


- Pond Stocking Rates: Quality Over Quantity 


Do not overcrowd your pond. This is really the bane of the hobby - most want to add that one more fish they fall in love with. But the reality is, over crowding is sure to cause problems at some point. Even if the water quality is good, when you start stocking over 3 lb. of fish per 100 gallons, you inviting trouble. Some people smugly break the rules but it catches up with them - your favorite fish can only die once, and their are no second chances


I have seen some misleading info regarding stocking on the web - recommending "inches of fish for a given area." This is bad advice. To illustrate the point, compare the mass of a small 1 inch long fish to a 1 inch portion of a 18 inch fish. Obviously the larger fish requires much more water volume and oxygen. The bottom line, use a stocking rate of less than 2 lb. of fish per 100 gallons of water to help stay out of trouble and give your system some tolerance for error. A 7" fish is about 1/4 lb, a 12" fish 1 lb, and an 18" fish 3.5 - 4 lbs.





Water, Water, Water  


- Water Conditioner:

Conditioner should be on hand at all times. This will give your fish a chance if you have a crisis and need to move the fish to a new holding system or refill your pond. And although conditioner has a lower freezing point than water, if it does freeze it will no longer work effectively 


I did an emergency health consult to find some dying fish and after many questions, discovered that the water conditioner used for the Spring clean out had been stored in the garage for the Winter. There was an instant positive reaction when I sprayed good conditioner in the pond as the fish immediately looked better 


In another scenario, I had client bring an ailing fish into the shop this past summer [2009]. It was July and the measured water temperature was 15, way below what it should have been. I discovered that the neighbour was running a hose into the pond every day for 2 hours, without water conditioner, to keep the pond "clean". Not only was it decreasing the temperature, the addition of chlorine and chloramines was hurting the fish 


Water Changes :

Less more frequently is the general motto for changing water, Also avoid a temperature change of more than 2 celsius. It is a great idea to perform water changes on a weekly basis. Monthly can suffice for well filtered ponds. It is better not to change too much water at a time - 10-20% is the norm

You need to be aware of the potential temperature change you will create. For example, if the pond is 10 degrees in Spring, a large 50%+ water change can be performed without ill effects. Since tap water is about 9 degrees, the net temperature change will be a negligible -0.5 degrees. However, if this same water change is performed in July, when the pond water temperature is north of 20 degrees, the resulting 50% water change will drop the pond temperature to <15 celsius. This will result is fish death I had a long time client make this mistake this past Summer when he dropped the temperature from 70 - 50 Fahrenheit. 13 of his 14 fish died. A horrible tragedy


Water Quality : 


Test your water regularly. The success of your pond will rest primarily with the water quality. Poor water qualitywill result in fish illness and possibly death. The big key to understand about water testing is that it will reveal potential problems before the fish show signs of distress. Strong fish may look fine for a long time in poor water quality. If water is tested regularly, poor conditions can be rectified before things degenerate


Test your water regularly. The success of your pond will rest primarily with the water quality. Poor water qualitywill result in fish illness and possibly death. The big key to understand about water testing is that it will reveal potential problems before the fish show signs of distress. Strong fish may look fine for a long time in poor water quality. If water is tested regularly, poor conditions can be rectified before things degenerate

Buy A Hose Timer: Stop Forgetting The Hose Is On


You will eventually forget the hose is on when you are refilling your pond - and this usually has dire consequences. If fish don't die, gills can be damaged and issues can arise shortly after. Every Summer several clients walk into our shop having had this preventable tragedy occur


We sell a volume based metered refill, in which you dial the volume of water you want to add [50-1600 gallons]. This is advantageous to the time dialed units as water pressure fluctuation do occur and it is hard to predict how long it will take time wise to fill properly. I use this refill on my own pond and in the Summer, just trickle fill the pond so asnot to change the water temperature. Our timer costs $30 which is far less than the cost of having to replace your koi collection


Filter Cleaning: Use Pond Water

Use pond water, not cold chlorinated city water when cleaning your filters ! We find clients are power washing their filter media on a weekly basis, destroying beneficial bacteria cultures. The pond water may be clear with this approach, but clarity does not mean it is chemically clean for the fish. The keys to filter maintenance are to clean the media with pond water and not to over clean


New Fish: Purchase And Introduce Cautiously

Fish get sick first and foremost from the inoculation of parasites by the introduction of an infected fish. Extreme caution needs to be exercised. This means you should quarantine or buy from a reliable source that has quarantined and performed a microscope analysis. Your water quality should be impeccable before adding fish, and new fish should not be introduced during the Spring when your current population is weakened from Winter


Murphy Had A Pond - You Need Backups

We all know mechanical failure is inevitable. We all also know about murphy's law [Mr. Murphy definitely had a pond]. But yet, so many people run their ponds on just a single pump. Of course the pumps quits when you have gone away or when you are unable to easily procure a replacement. The bottom line, have an air system running and consider having a backup pump on hand. Plugging equipment into different circuits is another common sense recommendation


Pond Pump Placement: Elevated Off The Bottom

We often hear of ponds being pumped out completely when a hole develops in the hose to the filter or waterfall. This is unfortunate and can leave the fish without water. If you pond is setup with a submersible pump in the pond, make sure to elevate it 8+ inches from the bottom. This also reduces the chance of your pump clogging with debris. Of course none of this is a concern if you set up the pond properly in the first place with a bottom drain



Algae: Changing Water Is Not The Answer

If you don't have a UV Sterilizer, your pond will typically experience an algae bloom during the Spring. The water turns green, sometimes very very green with visibility of just a few inches. The bloom will run its course and usually clear on its own. Changing the water and scrubbing the liner is not the answer, and is totally counter productive. This simply resets the cycle and destroys organisms that actually consume algae


Without a UV Clarifier, algae blooms will die back in time as your plants and filter mature. Additionally, make sure to maximize aeration as this drives out CO2, essential for plant photosynthesis. It also provides oxygen to the fish,particularly at night when the algae is consuming oxygen through respiration. Tips on controlling algae


Sick Fish: Get A Proper Diagnoses

If you keep fish they will eventually get sick. Being able to spot ailing fish quickly is paramount. Then you need to get a proper diagnoses. Unfortunately, buying meds based on mere conjecture can do more harm than good. Water testing and performing a mucous scrape to view under the microscope ensure you find out what is really going wrong. Ideally a slime coat analysis is done routinely with a scope so that small problems can be rectified immediately. This allows you to take informed action to correct the issue

Breeding Koi Fish: 


Breeding Koi page has a lot of valuable information. You may want to bookmark this page or print it out to have as a handy reference as you will use it often.


Breeding Koi and taking care of your Baby Koi can be an exciting process, watching nature at work, but it can be a hard job to do. Especially if you do not have a lot of time to watch your Koi. As you well know (if you already have Koi) they are full of surprises, and the same goes true for breeding Koi. Having given birth to a new generation, they would as willingly eat it as see it grow up. This attitude will continue until the baby Koi are maybe 3 in (8 cm) or larger in total length.


Correct nutrition makes a major contribution to the vitality and color of a fish, so supplement the normal diet of your Koi (while in the spawning tank) with good quality frozen foods, such as bloodworms and daphnia. Feeding these prepared foods will made up for any live foods that the fish are not eating wile they are in the spawing tank.


- Breeding Tips : 


Koi keepers who are committed to breeding should take the following to heart:

-Select Koi parents with the best attributes of their variety. Pretty Koi parents do not necessarily make pretty babies, so choose parent fish on the strength of their body shapes, good quality color, and good scalation rather than looks alone.

-Do not use show quality koi for breeding; they will suffer bruises, cuts, torn fins, and missing scales, as well as stress during spawning.

-Get both parent fish into prime health before spawning and again afterward.

-Cull the fry. Few varieties breed true, and every poor specimen must be weeded out in order to strengthen, not weaken, the gene pool.

-Don’t make errors. An entire breeding can be wiped out through carelessness and oversight.

-Keep notes and records for future attempts. Above all, do not expect a breeding to produce multiple champions.







Sexing Koi :


How to tell the difference between male and female Koi.


Many people wonder if their Kerry is a Kelly or if their Lola is a Larry because they are unable to tell if their Koi is a male or if it is a female. There are a couple subtle differences which will be explained. These are general facts that have been figured out over the years. Study your Koi greatly before you determine it to be a he or a she, many Koi have be mistaken for the opposite sex over the years!


- The Fins:


They are a Koi's means for propulsion. Female and Male Koi have different looking fins. Female fins tend to be larger, but will have less color. Female fins will have a rounded edge and will be opaque.












Male fins will have a pointy edge and will have a solid color look to them, like the two examples below.





Female Koi Fins .

 - Body Conformation :


Male and female Koi have different body conformations. Male Koi will be long and skinny, like a cigar, (its apparent with the Bekko on the right.) Female Koi will look more like a blimp, like the Aka Matsuba on the left. Female Koi get wider than male Koi because they carry tons of eggs. Many Koi collectors make it a point to only have female Koi in their ponds, since the large and wide body displays patterns much better. That is why most of the award winning Koi at shows are female.


Female Koi grow larger than male Koi.


This is the reason why: 


When the Japanese breed Koi, they pair a group of males to one female. They do this to get a wide variety of genetics, boosted immunities, and a nice selection of colors/patterns. Now, if you are going to breed one female with a bunch of large males, she is going to get pretty beaten up. This is not good, since a nice breeding female can cost more than a decent house. In order to prevent the female breeders from getting beaten up, they pair a large female with a bunch of smaller males. Since the process is repeated every generation, the males will always be smaller than the females.


Telling the Difference:



It is much easier to tell the differences between sexes when Koi get larger and older. When they reach sexual maturity, at around 2 years of age and around 12" of length, the females will fill up with eggs. This will give them the blimp look. When Koi are larger, it is easier to tell if their fins are pointed or rounded and if they are clear or opaque.






Female Koi  

Male Koi  

Spawning Koi : 


Even after careful planning, male and female Koi will sometimes swim around enjoying the company and not do anything until days later, when suddenly you least expect it they will have exhausted all their passion and, by the time you find out they will have already dined at leisure on their own eggs.


After the initial risk-stage (3in in length) has passed then Koi are extremely friendly with their baby Koi and any other fishes and they will not harm them.


The female will send out pheromones (a scent) which will drive the males nuts and finish the maturity of its sperm and the male will then chase the female. They can be seen constantly nudging the female. It may look like one Koi is being bullied by another Koi. This is quite a brutal affair because unlike most fish the gravid female koi cannot lay eggs they have to be driven out of her by a male.


Fish will come into spawning condition at the end of June or the beginning of July, depending on thewater temperature. Mating activity usually happens whenever the water heats up rapidly and is more apt to happen in the morning and evening hours.


Spawning (breeding Koi) will generally last only 20 to 30 minutes and can easily be missed. A good indicator that spawning has happened is to look for the presence of a froth or scum on the water’s surface.


Keep checking for translucent eggs, so they will not be eaten. Male Koi will be ready to breed when they are 2 years old, but females should be 3 years old. It is possible though that younger Koi will breed but their offspring will be of poor quality.


Eggs are spawn and sperm is milt.


The female is capable of carrying around 100,000 eggs for every 1kg of body weight. So a female of 10kg in weight will pass 1,000,000 eggs of which 60% will hatch.


Dependent on temperature, the egg will hatch in around 5/6 days but the poor little fry has not really had time to develop, but the longer it stayed in the egg the bigger the chance of being eaten, so mother nature again has equipped the newly emerged fry with only the bare essential but everything the fry needs to survive the next few days while further development takes place.


Koi and Goldfish will generally spawn just after or during an isolated warm spell as spawning time becomes imminent, you will notice the males chasing the females around the pond. This activity will get progressively more in earnest as the days go by and spawning gets closer.


Goldfish mate and produce young earlier than Koi. A Koi must be about 3 years old before he or she can produce offspring. Goldfish are the "hussies" of the pond and are always "going at it" no matter how old they are or what time of year it is. Koi, on the other hand, are more selective about the times and generally spawn only once or twice a year and it is during times of water temperature change or a heavy rain. It's not unusual for a group of Koi to spawn during a Koi show after being transported from their home pond and put into show tanks.

Spawning Tank


If you plan on Breeding Koi Carp you will need a spawning tank. A spawning tank can be any container that has dimensions of about 8x6 ft (2.4 x 1.8m) surface area and a depth of not less than 12in (30cm). Obviously if you plan to run a couple of females with perhaps 5-7 males then you will need a much bigger tank-in fact you will need a breeding pool, but this would be a bigger operation than the average beginner would contemplate. Make sure and put a spawning medium for the eggs to fall into. This could be any hardy aquatic plants, bristle brushes, or you can purchase spawning mops from your local dealer. Branches of conifers (evergreen tree or shrub) are also used and Spanish moss is a favorite choice for many koi breeders.

The medium is used purely to give the eggs something to stick on. Cover about two-thirds of the tank with the medium. After the Koi fish are placed in the tank the male will chase the female and bump her rear end to encourage her to shed her eggs for the Koi breeding to take place. The male will then release his sperm (known as Milt) it contains millions of sperm, only one sperm can enter one egg. This will normally happen in the early morning. Try to avoid disturbing the Koi breeding before and during spawning, but keep a careful eye on them, as the males may bully some females. If this happens, remove the female and place her in a separate pond.



When they have finished spawning, the females hang head down, respiring heavily, and the other fish will become less excited. Gently remove the spawning medium and carefully place them in a vat for incubation.


Baby Koi


For the next 3-4 weeks they should be fed liquid or powdered fry food.


It is very important that the rearing tank be clean as well oxygenated. After one month from hatching you may feed your baby Koi. How often do you feed baby Koi you may ask? The answer is frequently. Egg yolk is favored by many breeders. The main thing when feeding your fry is that the food be small, of high protein content and is fed many times a day. Remember, make sure and keep the water as clean as possible. Koi fry at the 'swim up' stage do not have any developed taste buds and so must detect their food by sight. Therefore they need to have food all around them.


Hard-boiled egg yolk is an ideal food for the first day or so - this has very little dietary value, but will increase the size of the stomach. Newly hatched brine shrimp (Artemia sauna) larvae are also a good food source for young Koi fry. Start feeding the brine shrimp when the Koi are about one week old. After another week or so, the baby Koi will be ready for a mash diet(the powder dust that is left after the manufacturing process of fish food). From this time onwards, feed the koi food of a size that can be taken by the smallest fish in the vat.


You will need to remove accumulated debris and waste frequently during this first feeding stage. A siphon made from aeration tubing is ideal for removing settled and suspended waste from the incubator, and an old toothbrush is useful to clean the outlet screen. You should also add fresh water regularly to the vat to remove nitrates and ammonia. Tap water which contains high concentrations of chlorine, should be aerated before it is added to the vat, to allow the chlorine to evaporate. After three or four weeks, the baby Koi will have grown to 5-l0mm(0.2-0.4in) in length and will be starting to take larger quantities of more generously sized foods.

koi quarantine tank..

THE Directory of Koi Varieties : 


Koi are a big part of Asian culture, but in the last few decades, the hobby of Koi keeping has spread across the world. Listed below are every original kind of Koi. Each variety usually has a Doitsu (scaless) version and a Gin Rin (sparkly) scaled version. These variations will be added as soon as we get a good photo. Click on each photo for a description of each variety.


-  Gosanke  : 


These three are the most popular in Japan, the Kohaku, the Showa, and the Sanke.


1- Kohaku Koi : 






 - Bekko  : 


The colored Koi with a black pattern..


1- Shiro Bekko

3-  Aka Bekko  : 

 -  Utsurimono  : 


The black Koi with a colored pattern.


1- Shiro Utsuri : 

 -   Asagi : 


The blue/grey Koi with a red pattern.



 -   Tancho : 


The Koi with a pattern only on their Maruten spots.


1- Tancho Goromo

2- Tancho Goshiki :



5-Tancho Sanke :

 -    Hikarimono : 


The metallic Koi with only one color for a pattern.


1- Nezu Ogon : 




3-Platinum Ogon :

4-Yamabuki Ogon :

4- Goshiki  :

2-Budo Goromo:

 -    Goromo : 


The Koi that have black shading over their patterns.


1-  Ai Goromo : 




 -  Hikarimoyo    : 


Koi that have metallic patterns.


1-  Kin Showa  : 




3-  Yamato Nishiki   :

2-  Aka Matsuba   :

 -  Matsuba  : 


These Koi have a grey shading pattern on their scales.



1- Shiro Matsuba    : 




5-  Karasugoi    :

3- Beni Kumonryu    :

2-  Kumonryu    :

 -   Kawarimono    : 




1-  Ochiba Shigure   : 




Where did all the Koi on this page come from?


Believe it or not, Koi are actually color-mutated food carp! Many years ago, the rice farmers needed a source of protein during the long and harsh winters in Niigata. They would keep the carp in ponds and grow them until they reached about 6 inches in size. Then the rice farmers would catch the food carp and would salt them so they wouldn't go bad during the cold winter months. The farmers noticed that some of the carp had different colors, so they kept these out and bred them together. Fast forwarda couple hundred years and now there is a vast array of colors! (Please Note: A common misconception is that the rice farmers would put the carp in their rice paddies. This is untrue, for the carp would have destroyed their crops! Consider the way Koi like to tear apart potted water gardening plants!)

Butterfly Koi

From Wikipedia, the free encyclopedia


Butterfly koi, longfin koi, or dragon carp are a type of ornamental fish notable for their elongated finnage. The fish are a breed of thecommon carp, Cyprinus carpio, which includes numerous wild carp races as well as domesticated koi ("Nishikigoi").


Butterfly koi originated in the mid-20th century as a result of an effort to increase the hardiness of traditional koi. Japanese breeders interbred wild Indonesian longfin river carp with traditional koi. The resulting fish had longer fins, long barbells, pompom nostrils, and were hardier than koi. These were known in Japan as "onagaoi" or "hire naga goi", or translated in English "long tail carp". Randy LeFever, the son of Wyatt LeFever, a noted breeder of koi, is credited with suggesting they looked like butterflies, a trait for which the breed is named. They are also sometimes referred to as Dragon Koi.


For clarification, the word koi is wholly inaccurate for describing these fish; Koi are, as dictated by the Japanese breeders, Nishikigoi, these long-finned carp are Hirenagagoi. The word koi has been given to these fish to increase their resale value and popularity in garden centres and the like.


-  Nishikigoi judging: 


Butterfly koi cannot be judged using the traditional criteria of used for koi judging. The standard criteria used in these events has evolved over many years, and they are specifically tailored to rate the characteristics of koi. According to an article in KOI USA magazine, the following characteristics are largely the basis for the unsuitability of butterfly koi in traditional competition:


Conformation – The ideal shape of a koi has been set by tradition to be generously oval. By contrast, butterfly koi are naturally more slender. This difference is amplified by the fact that traditional koi judging is done from a top-down viewing angle.


Relationship of fin to body – The ratio of fin-to-body is an important scoring criteria in nishikigoi competitions. By design, longfin embody a ratio that exceeds the standards applied to nishikigoi by 500 to 1000 percent.


Pattern differences - Great energy has been given to developing butterfly koi versions of traditional koi patterns, (e.g. kohaku, sanke, showa, utsuri and ogon). Butterfly koi, however, exhibit these patterns in a slightly different way.


For these reasons, Japan's airinkai (an organization that sanctions Japanese nishikigoi hobbyist competitions) have disallowed butterfly koi from competitive judging for many years; the UK Koi Judges Association also excludes these fish from competition although their American counterpart the American Koi Club Association (AKCA) has (as of June 2006) reportedly created new standards for judging butterfly koi at future AKCA competitions.





- Popularity   :


Butterfly carp are strongly disliked by many keepers of traditional koi who view the breed as inferior to koi, even though all koi are the result of continuous inbreeding whenever a new recessive gene showed itself over the centuries. The dislike of butterfly koi by some traditional keepers may be the reason why most reputable koi retailers do not sell butterfly koi, and why most of Japan’s famous and most prestigious breeders do not breed butterfly koi today. They are largely unpopular in Europe and Asia, but are popular with new hobbyists for a short period of time and in North America where they are more readily available. The popularity of these fish in the North America has earned them the nickname American koi.


However the butterfly is growing in popularity worldwide and is very popular with many pond lovers who do not view it is as a threat or poor comparison to the very beautiful traditional koi, more as a different but equally lovely cousin.


Examples of Butterfly Koi are becoming more widely available as demand grows, seeing many variations in colour and quality emerge.


As A breed of fish in their own right the Butterfly is a very majestic and beautiful fish, bringing grace to the pond, they have very similar traits, feeding requirements and habits to Koi so can be kept along side them happily.


Hopefully the future will see them recognized for this, enabling them to come out of the shadows of judgment from the koi world and into the light of appreciation for what is a magnificent fish.



 Koi Poster : Quick guide for koi koi varieties  .

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