28/02/2020
Received countless of messages asking on what to do with their sick koi collection. Hobbyists tend to forget the most important thing to do before introducing new koi to pond - QUARANTINE.
"It is a fact that throughout the history of fish keeping there has always been a possibility that the introduction of new fish to an existing pond may mean the introduction of a disease or parasite infection. This is not a foregone conclusion as many new fish have been introduced to koi collections without any problems what-so-ever. Therefore, purpose of quarantining is to protect your collection. Let the Buyer Beware.
Koi keepers should always check the ponds where they intend to purchase from. Any dead koi, signs of stress, koi lying on the bottom, gulping at the surface etc should be viewed with suspicion. Once you have made the purchase and taken delivery, NEVER take for granted that the fish you purchase from ANY source are perfectly healthy. This is not pointing a finger but simple common sense to protect the most important person in koi keeping - you. Protect yourself -quarantine your own fish, if possible.
The most effective way to protect a valuable collection is to prevent the introduction of diseases. NO fish should be added to a collection unless they have been adequately quarantined by you, the koi keeper. You must be reasonably sure the new purchases are not carrying any diseases and/or parasites. They should also be quarantined to allow them to rebuild their strength and immunity. This quarantining period does not have any fixed time, but should be a minimum of a few weeks. Stressed, weakened koi will, in most cases, be open to attack from micro-organisms (e.g. bacteria and fungus) and macro-organisms (e.g. parasites). Therefore, as a precaution koi should be disinfected before adding to a collection. EVERY koi you purchase must be viewed as a potential carrier of disease simply because ALL koi carry pathogens (pathogen = something which causes a disease) and some parasites. Stress plays a major role in triggering diseases. The 'passengers' start multiplying. If the koi is weakened by stress, it will not usually be able to cope with this increase in parasites and/or bacteria and an infection will result.
Koi, like all creatures, develop a specific immunity against the pathological agents (bacteria, fungal or other micro-organisms that will harm them) in its own pond. In other words, the koi become accustomed to them. When this happens, equilibrium is established. To put it another way, there is a mutual agreement between the koi and the organisms that live on it and around it in a common environment. Just as there is a mutual understanding between our bodies and the micro-organisms that live on us. We are very dependent on these friendly creatures, but, if our resistance is lowered for some reason, the friendly 'bugs' can explode with a resulting infection.
INTRODUCING NEW KOI
When new koi from other regions or other ponds are introduced, they bring in microorganisms which they themselves have become immune to, but they may not be
immune to the bacteria already present in the water or on your koi. The koi in your present collection may, in turn, not be immune to the new bacteria brought in with the new koi. For example, different strains of Aeromonas bacteria can cause cross infections. Koi A has become immune to bacteria type "a" that has developed in its own pond or dam. Koi B has become immune to bacteria type "b" in another pond or dam. If we place them together, bacteria type "b" infects koi A and naturally bacteria "a" infects koi B. In other words the equilibrium is broken and if the bacteria is a virulent strain that your fish are not immune to, an infection can be result.
YOU MUST QUARANTINE
The definition of quarantine is: "A period of time, originally lasting 40 days, of enforced isolation or restriction of free movement imposed to prevent a contagious disease from spreading." This idea of enforced isolation can be used on fishes moving from country to country and also from area to area within a country.
It is not important whether the koi are moved from Japan to Philippines or moved from Cebu to Manila or even moved a few kilometers down the road. When you receive them, it is preferable that YOU must quarantine your new koi and observe them. Fortunately, in most cases there will not be a problem. But, be prepared and observe
the new fish regularly. When you are sure they are healthy you can introduce them to
your present collection. There are many instances of people buying fish that have never been quarantined and introducing them directly into their ponds without any disease being spread. These koi keepers don't believe in quarantining their new koi because they believe that it will involve moving the fish twice and therefore, involve more stress. The facts are you may be lucky and you may not be lucky. If koi are quarantined for any length of time it stands to reason that those fish in the
quarantine tank develop their own biological balance and eco system. The longer the quarantining period the more chance of this happening.
All quarantine procedures have two things in common.
When you purchase new koi –
ISOLATE them from your present collection for a period of time, even if the supplier states that he has quarantined the fish,
OBSERVE them until you are satisfied they are strong, healthy and free of disease. You need a separate pond or holding tank with separate pumps and filters as well as good oxygen levels and facilities to change water regularly. Also separate siphon pipes, nets and equipment that should not be used on the main pond. Covers may be necessary to prevent the koi jumping out. Mature water is essential. Add a low level of salt as a stress reliever. Avoid high levels of salt as this will add to the stress the koi are already under. Oxygenation levels are critical and must be high. Circulation, air stones, venturies, waterfalls etc. The koi need to be rested. You must know the capacity of the quarantine tank or pond. This helps if you need to medicate.
Any type of pond or container will do. Avoid galvanised baths. New ponds must be rinsed thoroughly. To assist the new koi to adapt to your environment use water from your main pond to change the water in the quarantine pond. In this way the new fish will come into contact with the strains of bacteria etc in your pond. On the quarantined pond there will be NO bacteria in a new filter no matter how large the filter is unless you have seeded the filter media beforehand. Ammonia can build up rapidly when a large number of koi are kept together in a new pond system. This will add to the stress factor. Ammonia and nitrite levels must be monitored every day in quarantine ponds. Reduce ammonia levels with water changes and possibly zeolite or seed the filter with mature filter media from another pond.
The temperature difference between the bags and the quarantine pond must be equalized to avoid any stress. Float bags if water temperatures vary more than 2 or 3 degrees between the bag and the pond. The pH in the bags and the pond will be substantially different. A lower pH (more acidic)
can be anticipated in the bags. pH must be adjusted SLOWLY over a period of time. Water from the pond can be gradually added to the bags to equalise the pH. The water from the bags must never be added to the pond as there could be parasites or pathogens in this water. Discard this water onto the garden or add chlorine to it before throwing down the drain. Most disease and/or parasite infections will manifest themselves with in 10 – 14 days. Internal problems brought about by the catching, bagging and transport of the koi may take months to reveal themselves. Quarantine for as long as is necessary for YOU to be certain that there is no outbreak of
disease or parasites amongst the new koi. Several weeks is usually considered the minimum. Other koi keepers consider several months to be best.
Only add medications if necessary. If the koi are healthy let them regain their strength then treat for parasites as a precaution. Alternatively introduce them into the pond then treat the whole pond for parasites. One of the main reasons for quarantining new fish, especially fish that have spent many hours travelling plus the stress of being caught and handled, is to give them time to rebuild their strength and immunity before introducing them into a collection. Imported koi are very stressed because they have probably been starved for several weeks prior to shipping. They spend over 25 hours in crowded plastic bags. You must treat them carefully. Feed them lightly on a high quality food. Let them rest and regain their strength. Feed lightly once a day at first. This will keep ammonia levels down and gives the koi a chance to get their digestive systems going again. Add one or two of your low quality “disposable” koi from the main pond into the
quarantine pond for about 2 weeks before you want to add the new fish to the main collection.
IF YOU DO NOT HAVE QUARANTINE FACILITIES
Be aware of the ever present risks of introducing new koi into an existing koi collection. There are many koi keepers who do not have quarantine facilities so they introduce koi directly into their collections. This is very risky but a common practice amongst koi keepers. The whole collection and pond would have to be treated as a quarantine pond and the whole collection must be closely observed every day for the first few weeks.
Many koi keepers give new koi a strong bath of Potassium Permanganate or salt before introducing new koi into their present collections. Note these dips will not stop KHV. The koi must be observed at all times during the short baths. Never leave the koi to answer the phone or speak to someone. The few seconds between successes and
disaster is very fine. Move the koi gently from the dip directly into the pond. At the first sign of sick fish – perhaps blood vessels showing in the whites of koi,
extreme agitation, flashing, or becoming lethargic, fins clamped, koi lying at the bottom, koi hanging around the water fall the cause of the problem must be identified before action is taken.
The whole pond will have to be treated correctly. Know your pond volume. Have someone to contact quickly if you need assistance."
The article above is super easy to understand. I hope this will somehow enlighten some hobbyists as to how important it is to QUARANTINE our new fish. PREVENTION IS BETTER THAN CURE.
Live the Koi Life!
**Credit to Christopher Neaves of SAKKS
