Ki Utsuri

 Quick Care Facts

• Care Level: Moderate   • Temperament: Peaceful   • Maximum Size: 28 to 40"
• Minimum Tank Size: 500 gallons   • Water Conditions: 55-79° F, 34-85° F temporary water conditions
• Diet: Omnivore   • Origin: Japan, selectively bred carp   • Family: Cyprinidae
• Species: Koi, Nishikigoi/錦鯉 (Japanese)   • Aquarium Type: Pond

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The Ki Utsuri is derived from the cross-breeding of a Magoi or black Koi and a Ki Bekko Koi, thus it is a black based koi with large yellow markings common to Utsuri specimens. Many people associate the pattern of the Ki Utsuri with a checker board pattern or sometimes simply a bumblebee look. Despite how one views the coloration of the Ki Utsuri, it is a unique looking Koi who is certain to attract plenty of attention.

Ki Utsuri is the third most common of the primary Utsuri types, with the Shiro Utsuri being the most refined and common and then the Hi Utsuri who is somewhat common and becoming more refined as the hi (red) coloration is being steadily improved upon by breeders. The Ki Utsuri is the least refined of the Utsuri lineage; however, like the Hi Utsuri is now being further refined by breeders to deepen the black coloration and sharpen and brighten the yellow markings.

The Ki Utsuri and to a slightly lesser extent the Hi Utsuri tend to have a more flat charcoal black, and it’s common for them to develop small black specks within the yellow or orange patterning. Because of the refinement of Shiro Utsuri it’s hard for Ki Utsuri to compete head to head with them in koi shows. The Ki Utsuri holds its own though in the pond as a uniquely beautiful Koi that always grabs attention.

The Ki Utsuri comes in two types: a standard skin yellow and black, and a metallic skin yellow and black, which is called a Kin Ki Utsuri, Kin being the metallic skin, and Ki being the yellow, and Utsuri being the black base. The color yellow in koi does better without a lot of color enhancing feed. A Ki Utsuri that is fed foods high in color enhancers such as spirulina can develop orange spots within the yellow patterning, and the yellow color in general can be pushed more toward orange with foods high in color enhancers. The black color will show itself more vividly in ponds with harder water and higher pH.

The following traits are essential for quality Ki Utsuri Koi specimens:
 
The black base coloration of the Ki Utsuri should be as close to lacquer-black as possible and should have smooth edges where the black and yellow colors meet. Small black dots or blotches where the colors meet is a flaw for this variety.
 
The foundation of an Utsuri is the sumi (black), thus it needs to a solid dark black color and be well balanced across the entire body and face of the fish. Black on the face of the fish covering the eyes or the mouth, in a v-shape pattern or a menware lightning pattern is highly desirable for high quality Ki Utsuri.
 
The base of the pectoral fins of a Ki Utsuri should be black with the rest of the fin being red. This black base area of pectoral fins is known as 'motoguro', with the more defined and confined to the base it is, the better. All black pectoral fins or pectoral fins that are almost all black are fine as well.
 
The overall balance of ki (yellow) with sumi (black) should be either balanced or favor the sumi, as the Ki Utsuri is a black based fish and should have ki that accentuates the deep, lacquer black base coloration of the fish.

Caring for and keeping Koi is tightly tied to the pond in which they live, as the keys to successful Koi keeping revolve around water quality, proper filtration & aeration, quality food and protection from predators. First things first when keeping Koi and that is simply that they get big and need a pond to match. Depending on the number of Koi one plans to keep they need to build a pond that is up to the task of keeping a group of 24" to 30" on average fish that can reach a body mass nearing 30 lbs! While bigger is better, a few rules that will provide a good minimum starting point for an adequate Koi pond include the pond being at least 4 times the length of an adult Koi and 3 times the width, with a depth of around 3 feet. While modern filtration can keep fish alive in very small amounts of water, some reasonable swimming space is required for such large fish and they need some depth to be able to regulate their temperature by swimming closer or further from the surface of the water depending on temperature.

Koi like their common carp ancestors are a cold water fish capable of living in temperatures ranging from the mid 35° F to 84° F they are considered a hardy fish species. However, Koi do not do well if kept at extremely warm or cold water temperatures for long periods of time. They prefer water temperatures ranging from 50° F to 78° F (10° C - 25° C), where they are in ponds that are deep enough for them to regulate their body temperature as they see fit by swimming higher or lower within the pond. The exact ideal depth for a pond depends greatly on the climate where the pond is built, warmer climates can have ponds as shallow as 3 feet in depth, where colder climates will need at least 5 feet deep areas to allow the fish to survive cold winters.

While Koi are fairly hardy fish in general they are selectively bred over hundreds of years for color and pattern, which has made them less hardy than their native carp cousins. Koi are especially sensitive to low oxygen levels and high levels of nitrate in the water. Therefore, proper pond filtration is critical to maintaining high quality water which is crucial to Koi health and longevity. Proper Koi pond filtration should provide high levels of dissolved oxygen, excellent mechanical, biological and chemical filtration and provide parasite control via a UV sterilizer. Partial water changes or the use of plants as a vegetable filter should be used in order to export or remove nitrate from building up in the water.

Second only to the pond design and water quality, Koi need high quality foods that provide them a mix of meaty and plant based food items that will provide a balanced and nutritional diet. Koi should be fed different foods or not at all based on the water temperature and time of year. In the Spring and Fall where water temperatures are between 55° F - 68° F (12° C - 20° C) Koi should be fed foods lower in protein and more easily digestible. When water temperatures are above 68° F or 20° C, then can be fed higher protein foods.

The pond design is also critical in terms of protecting Koi from predators and harsh water temperatures. Ponds that have gradual sloping sides and are shallow in depth allow predators to easily wade into the pond and feed on the Koi within. Also shallow ponds, especially those without shade provided by pond structures or overhead vegetation make it difficult for Koi to avoid the intense sun and high water temperatures during summer months. Koi ponds should have sheer edges that drop down quickly to 2 to 3 feet in depth to deter predators and should have areas of the pond that are deep enough to avoid predators and excessive winter or summer water temperature extremes.

Koi being bred from Carp are an omnivorous fish species, who with their down turned mouths typically eat food items that they scavenge for on the bottom of their natural pond, lake or river homes. However, as Koi are selectively bred in captivity and raised in well maintained ponds, they have adapted to eating food from the surface of the water and will readily consume a wide variety of commercial floating foods designed for Koi.

Many Koi keepers prefer to feed their fish at the surface of the water as it allows them to bond with the fish by training them to hand feed and gives them a chance to inspect the fish for any signs of disease or any wounds brought on from pond predators like raccoons, herons or foxes.

Koi will readily consume a wide variety of natural foods in addition to balanced commercial Koi foods, these include: lettuce, watermelon, peas, oranges, squash and fresh seafoods like prawns, shrimp, scallops, squid, chopped fish, mussels, etc. as long as it is fresh and not pre-cooked or preserved in any way.

Koi should be fed different foods or not at all based on the water temperature and time of year. In the Spring and Fall where water temperatures are between 55°F - 68°F (12°C - 20°C) Koi should be fed foods lower in protein and more easily digestible. When water temperatures are above 68°F or 20°C, then can be fed higher protein foods. In the Winter when water temperatures are below 50°F or 10°C, the digestive system of the Koi will slow nearly to a halt and they should not be fed directly, they may nibble a little on plants and algae, but won't need direct feeding.

Feeding Koi when the water temperature is below 50°F or 10°C runs the risk that any food eaten may not be fully digested and will rot inside the gut of the fish causing illness and possibly cause the Koi to die.

Koi, just like standard Carp when bred naturally will spawn in the Spring and early Summer. Spawning is initiated by the male who will begin following the female about the pond, swimming right up behind her and nudging her repeatedly. After the female Koi is stimulated and releases her eggs, they will sink to vegetation, spawning mobs or even rocks or gravel on the bottom of the pond. The male will release sperm into the water and the eggs will become fertilized and begin developing. Although the female produces large numbers of eggs, many of the fry do not survive due to being eaten by other Koi or because they are not properly fertilized. On average if the egg survives it will hatch in around 4-7 days.

Most pond keepers looking to spawn their Koi will use mop heads or specialized Koi breeding mops in order to be able to control where the eggs are hatched. Since Koi will produce thousands of offspring, of which only a small percentage will carry the proper coloration and pattern necessary to be considered Nishikigoi or Koi. The rest of the offspring will be brown, black, grey or mottled in color and have little to no real color pattern. Professional Koi breeders will cull these undesirable offspring and only raise up the fish that show the desired coloration and pattern.

Nurturing and culling the resulting offspring or "fry" as they are known is a time consuming and tedious job, typically only done by professional Koi breeders or farms. The difficulty in raising quality Koi is in the continual process of feeding, sorting and culling the fry for months on end, while also needing to continually move desirable fish to new and larger holding ponds as they are grown out. Koi breeding at a minimum requires maintaining multiple grow out ponds, having many different types of foods on hand (including live or frozen foods) and performing sorting and culling duties every few weeks for the first year or up to about 6 inches in size. The resulting "Tosai" or yearling Koi will vary in quality from lower pond grade all the way to varying levels of high quality Koi.

While quality parent fish, high quality water conditions and foods provide reproductive advantages for Koi breeders, the semi-randomized results of the Koi reproductive process means that it is possible to get a favorable result even for novice breeders. Additionally the variability in the reproductive process allows for new varieties of Koi to be developed within a relatively few number of generations.