Buying healthy Koi
Koi keepers may think buying Koi is all about body shape, skin quality, colour conformity, pattern and lustre. Knowing what you are looking for, and searching for the degree of perfection you can afford, in a particular Koi variety, reveals the patience and judgement needed to own an amazing Koi collection. None the less, there are several pitfalls for those new to hobby of Koi keeping. Whilst targeting the novice, this article also serves as a reminder to experienced Koi-keepers, that caution is needed in any hobby that focuses around a live animal.
A specialist Koi dealer settles his Koi after their long plane flight, and later examines and treats them for any health problems. He then allows the mucus to re-establish, and ensures they are as healthy as possible before displaying them for sale. No dealer should do less, although biosecure dealers carry out a longer quarantine with several possible stages. Consider that having prepared their Koi for sale dealers take on trust that hobbyists know how to care for them. Sadly, not all Koi keepers are fully prepared and dealers cannot question everyone who visits their premises. It is likely they will discreetly question new customers, to ensure their pond is not overstocked, and they are aware of the vital role of good water quality in Koi well being. In addition, most dealers will suggest introducing new Koi slowly one to two at a time to any new pond, so that the filter biology can grow to cope with the waste products, new Koi will create. Koi excrete a lot and the care they need exceeds that of Goldfish and other pond fish species. It is a legal requirement in the UK that the seller of any animal knows the purchaser can care for it, and that includes Koi. What matters about a Koi outlet is the experience of the staff. Irrespective of whether you favour an aquatic centre, or a home based Koi specialist, do not be mislead by the décor, or the lack of it. Also, keep in mind a free bag of Koi food is an incentive to purchase, not an assurance of healthy Koi.
Tank and Koi conditions
The conditions Koi are housed in when displayed for sale should never be overcrowded as this creates stress in the Koi, and increases the risk of disease. Large amounts of waste matter visible on the bottom of tanks or ponds are a sign of poor management. Discoloured water in tanks in which fish are offered for sale suggests they are under treatment and should be avoided. Algae or moss growing in the tanks or filtration systems in trade outlets is something Koi keepers do not expect to see. However, this is normal and Koi enjoy having a little blanket weed on the walls. In a sales tank, signs of lethargy, irritation, or ulceration in the Koi are a sign of bad practise. Carp pox that causes the shiny wax like growths is unavoidable in Koi, although it rarely becomes a serious problem. When choosing Koi observe that the gill covers touch the body as they close, and that all the Koi in a tank have a similar gill rate. It sounds obvious not to buy fish with any abnormality although Koi keepers do. An abrasion may not be visible and could become a problem later. Inspection bowls should be available and netting limited to those Koi you are likely to purchase, as a better inspection is possible in the plastic transport bag.
Avoid Koi with split or damaged fins
The fins in Koi can be damaged by netting, handling, or ammonia burn in transit, and split fins are often seen in trade premises, particularly in small Koi. A clean split may heal without intervention, although the fin membrane can become infected. The ventral and anal fins are often inflamed if Koi spend time on the bottom of the tank, and they are easily infected. When all the fins are deteriorating, this suggests systemic disease and treating the fins with an antiseptic product will not be effective. Higher water temperatures help fins regenerate, although, raising the temperature also encourages bacterial infection. The novice therefore should avoid all Koi with damaged fins. However, those more experienced may learn to tell these various conditions apart. For example, a clean split in fin membrane with no inflammation stands more chance of healing perfectly.
Origins, age, and gender
Koi nowadays are well travelled yet without a passport or a medical record card and only the elite Koi have a pedigree. Breeding is a different skill to rearing and fry are often bred in one country and reared in another. Their nationality and date of importation suggests how acclimatised a fish is at the time of purchase. Every Koi is unique in respect of their genetic history and acquired immunity. The longer a dealer has stocked a Koi the safer that fish is in respect of certain health risks. Those Koi keepers who breed or show their fish need to know the age of a Koi, to assess when the fish reaches maturity. The owner can predict when the Koi will be ready to breed or will be in show winning condition. Some Koi-keepers keep their male and female Koi in separate ponds for greater control. The prime reason for such segregation is to prevent the damage that females endure during spawning in mixed sex ponds, if the ratio of males to females is not balanced. It can be difficult to tell males from females particularly in small Koi. The females are more evenly rounded towards the rear of the body, unless they are full of eggs, and then their expanding outline makes their gender obvious. Female pectoral fins are smaller and less well defined than in male Koi, who have larger pectoral fins, and a more streamlined or torpedo body shape.
Koi Herpes virus
Koi Herpesvirus (KHV) is in most Koi producing countries and all trade premises no matter how well maintained cannot avoid cross-infective risks. This is due principally to the various possible origins of the Koi and their stocking density. If all the Koi are Japanese, they may be from numerous farms, or may have been mixed at the centres that prepare Koi for export. Israel now vaccinate some but not all of their Koi production against KHV. Such fish can pose a slight risk if introduced to a pond in which the Koi are unvaccinated. It is impossible to quantify this risk as it depends on the methods used during the vaccination process. Irrespective if Koi are champions or pets, it only takes one new fish to introduce disease, and for this reason, it is safer not to mix nationalities. Koi from Japanese farms mix well although the prime issue is could any Koi carry KHV and health certification is not a guarantee as it is currently applied. Whilst English bred Koi can be introduced to a pond of Japanese Koi, it is better not to house vaccinated Israeli Koi in the same pond as Japanese or English Koi. However, a pond comprised only of Israeli bred Koi will be extremely hardy although when stocking keep in mind not all Koi from Israeli farms are vaccinated and you should not mix them with unvaccinated Koi.
When at a Koi show and thinking or purchasing Koi, buy only Koi from dealers you know as a precaution. It is safer to visit the premises of an unknown trader before purchasing. Buying Koi online with unknown origins is also a risk, as such Koi are often the source of serious disease. However, once you know a dealer is genuine, buying online or at a show becomes safer. There is no guarantee of disease free Koi from any source no matter what claims are made. There is no standard approach to quarantine by the Koi trade. A uniform biosecure quarantine process was set up by LFH for the Professional Koi dealers Association. One of the major issues is that not all premises can adapt around the requirements and this results in various levels of biosecurity that is not what LFH hoped to achieve. Although the Association is now closed the LFH Biosecurity Protocol is still adhered to by several Koi dealers in the UK and other countries. Following the LFH protocol is not easy although it lowers all disease risks and this can be proven statistically. In an ideal world, I am sure hobbyists would favour this level of protection.
Variety is the spice of life
The novice Koi-keeper often blames a dealer when something goes wrong only to discover when more experienced the dealer was not at fault. Most hobbyists appreciate that a good relationship with one Koi dealer creates a solid foundation for the hobby. Confusion arises particularly for those new to the hobby when two or three dealers are consulted and each recommend a very different approach to just about every aspect of Koi-keeping. It is the advice on how to maintain the pond for the day-to-day welfare of Koi and how to treat health problems that can differ so much. Dealers are bound to favour the pond treatment products they sell and that means they have experience in using them. The road to healthy pond does not have to follow an identical route as long as what is suggested works. However, the issues that should remain the same are the scientific, biological, and medical principles that underlie the Koi-keeping hobby. Dealers will be the first to say they cannot know all the facts as these are complex and technical subjects although they naturally talk about all things Koi related.
Getting new Koi home
Always use a box never transport Koi in just a plastic bag. Obviously, the bag can burst and being inflated with oxygen, it goes with a bang if hot cigarette ash is in contact. A box affords greater insulation against temperature fluctuations and keeps the Koi calmer for the journey home. Position the box transversely across the axle in the car boot to minimise the motion of the water, and cover the box. Koi are naturally a little stressed at shows as such events involve recent transportation and fluctuations in all their water parameters. This commonly triggers off white spot a parasite often carried by Koi sub-clinically. Temperature changes make this a common health problem in Koi either purchased or exhibited at shows. Minimising stress and temperature fluctuations on the journey home and during their introduction to the pond will help but do keep an eye out for signs of white spot.
Introducing Koi to the pond
No Koi dealer can complete the full process of acclimatisation for any Koi. Fish have to assess each new environment they live in no matter how temporary it may be, and make adjustments that involve complex biochemical reactions until they fully adapt. Only after this process is complete is there less risk of stress related health problems. The time scale for full acclimatisation varies fish to fish and is influenced by everything the Koi have experienced, even temporarily, before reaching their home pond.
All a hobbyist can do is support their new Koi by carrying out the partial acclimatisation. This is the first stage of a long period of adjustment that begins when the fish are floated in their transit bag to equalise the water parameters in the bag with those in the quarantine tank or pond, depending on where the Koi will be housed. Once the water temperature is the same gradually introducing a little tank or pond water into the bag, until the pH is also identical before releasing the fish helps to alleviate stress. Always discard the water in the transit bag, as it will be full of ammonia and other waste products. In very hot weather, the oxygen in the bag may become depleted, and the floatation is then more safely carried out in a bowl instead of the bag. This also applies if the bag is no longer fully inflated after a long journey home or the fish is distressed. The partial acclimatisation minimises the initial shock of being netted, bagged, and transported to an alien pond. All Koi will appear to cope initially with the experience although it is more traumatic for some. It is better to allow new Koi to settle for several hours before offering food. It is often thought that if new fish eat they have settled in when this is not the case, and there are good reasons not to feed Koi until the initial stress has diminished.
Healthy Koi are priceless
Off colour is a good description when Koi are sick, as their normal skin colouration and lustre are reliable indicators of good health. In behavioural terms shoaling together, vitality, an erect dorsal fin, and a good appetite are all positive signs of well-being. As well as beautiful Koi, a pond needs fish with personality. In all the Koi varieties it is mainly the Chagoi family that pass on their trust in humans to their companions, creating a pond of tame pets. The qualities Koi possess that make a hobbyist want to give a particular fish a home will always differ considerably as, beauty will always be in the eye of the beholder.