Keeping Koi is one of the most fascinating hobbies. Relaxing next to the pond watching the fish swim about lazily is a very pleasant occupation. There is so much to learn and appreciate, that the Koi keeper can spend many hours researching the subject. Large Koi can become extremely tame, and will learn to eat from one’s hand. Often the Koi develop particular personalities and behaviour patterns.
The first Koi
Koi originated in China about 2500 years ago, when the word was first used to describe the fish. There are different versions of the story, one saying that Confucius was given a fish named “Koi”. The other story is that Confucius named his son Li (literally meaning Koi) because he wished his son to be as orderly as the arrangement of scales on the back of the Koi. Koi were also considered to be a symbol of strength.
These early Koi were carp, and bred from the Magoi or black carp line. The first mentions of coloured carp occur in manuscripts from about AD 250 that tell of red, white and blue coloured carp.
The early mutations from the original black fish would have been red or white and cross breeding would have resulted in a Koi much like the Asagi (blue-gray and orange/red) of today, since the Hi (red) appeared on the belly of the fish. Later, a white fish with red on its back was developed which became the modern Kohaku.
In Niigata Prefecture, a beautiful, mountainous region of Japan, Koi were first bred as a food source. The inhabitants were often cut off from the outside world by snow during winter. Today, it is the home of many of the finest breeders of Koi in the world. The secrets of breeding have been passed down from generation to generation.
Modern Koi varieties
Koi breeders in Japan have now developed many different varieties.
The most popular varieties are: Kohaku, Sanke, Showa, Bekko, Utsurimono, Asagi, Shusui, Koromo, Goshiki, Tancho, Kinginrin, Kujaku, Chagoi, Ogon, Ochiba Shigure and Hariwake.
The names of Koi can confuse the novice totally, as within each variety, mutations showing Doitsu ( no scales) Koi with metallic lustre such as the Ogon and Kinginrin ( shiny scales) add to the vast array of wonderful Koi that are available today to the dedicated collector. It is not surprising that a beginner wonders if the names will ever be mastered. However, with the help of a knowledgeable dealer, the mysteries of Koi can easily be grasped.
Find out more about these varieties in this article.
When selecting Koi for your pond, it is important to decide whether you plan to keep Koi purely as a hobby or whether you want to become a collector with only top grade fish. Shiny, brightly coloured Koi, such as the Ogon, Kinginrin, and Doitsu varieties, will often attract the novice.
A balanced collection will have as its basis, a number of Kohaku (red & white) Sanke (red, white with a little black) and Showa (black, red & white). There will also be a selection of other varieties giving colour and balance to the collection.
Rather try to buy the best quality small fish, which has a good future, than numerous cheaper, inferior fish. A fish that is not good as a baby does not have much chance of becoming beautiful in later life. It is however, important to know that in some varieties, small Koi that are good quality, do not necessarily look good until they have matured. These are called “Tategoi” meaning Koi with future potential. Again it is important to get sound advice from your dealer or Society, (Details are given below) who will assist with selecting the best Koi.
KOI KEEPING – BASIC PRINCIPLES
It is important to provide the correct environment for you Koi so that they will thrive and so that you will enjoy rewarding, hassle free Koi keeping.
• Ensure that your pond is a minimum of 10,000 litres in volume (preferably larger) and not too shallow (an optimum depth of 1.5m is recommended). Koi will quickly get too large for a small water feature. It would be advisable rather to keep goldfish in smaller volume ponds.
• A Koi pond needs both mechanical and biological filtration to keep the water healthy. Biological filtration is the natural means of removing toxic chemicals from the Koi pond. A good filter will also remove the food source for algae, which will ensure a pond with clear, healthy water.
• The circulation of the water by means of a pump, through the filter and returning via a waterfall or venturi, will create the necessary aeration to supply Oxygen to your fish and the filter. Your pump must run 24 hours a day.
• Water in a new pond system should be de-chlorinated and the PH stabilised before adding fish. The above is true for any future water changes. Rainwater can also affect the PH. The PH should be between 7 – 8.5.
THE NITROGEN CYCLE
The Koi keeper will need to test for the following in their Koi Pond in order to establish that the water quality is suitable for their fish.
• AMMONIA – a metabolic waste product excreted through the gills of the fish, and through the decomposition of organic matter. A high concentration of Ammonia will be toxic to fish. If toxic levels are reached, immediate action is needed. Stop feeding, do a water change and check that your filter is working. Remember to de-chlorinate the water when changing water. If the Ammonia levels remain high it may be that your filter needs to be up-graded. Please contact Koi @ Jungle for advice.
• NITRITE – produced by the oxidation of Ammonia by aerobic bacteria (in your filter) or by the reduction of Nitrates by anaerobic conditions (heavy layers of organic matter in the filter or pond)
• NITRATE – not acutely toxic, but detrimental in high concentrations in the long term. Nitrates can be corrected by frequent small water changes and by having a stream with water plants, which utilise the nitrates in the water.
• PH – ideally should be between 7 – 8.5. Koi will suffer if the PH drops below 7. Highly acid pond water will cause loss of appetite, listlessness, or a white film on the scales and in some cases death. A low PH can be corrected using Bicarbonate of Soda or using crushed coral in the filter. A very high PH is not advisable either. In this case, please do not attempt to correct with pool acid, but rather choose a more natural product such as peat moss.