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Purifying the water of Koi ponds with Virkon S®

Virkona duoVirkon® S is a disinfectant and works from 0 degrees. It kills pathogens, lowers the germ count, fights viruses, bacteria and fungi.

There are 2 very serious viral diseases: “Koi Herpes Virus” (KHV) and “Spring Viraemia”. As with all viral diseases, no specific treatment is yet possible. However, support measures combined with Biosecurity measures, as is applied in animal husbandry, ensure that the virus cannot spread. That is the maximum that can be achieved.

To prevent Koi failure and help reduce any viral diseases, we have developed successful Biosecurity programmes. These programmes help improve the health and welfare of Koi and are also used in commercial fish farms.

What is Virkon®?

Several viruses, including ‘Herpes’ are serious threats to Koi owners. Many fish are carriers without showing any signs of it. When these carriers are brought into contact with susceptible fish, if there are stress situations, they may secrete the virus into the water, which will lead to infections and very high fish mortality. It has been independently proven that Virkon is highly effective against significant fish diseases/pathogens. A very important property for application in koi ponds is that Virkon greatly reduces the level of pathogenic bacteria and some protozoan parasites in the water.(bacterial pressure).

Koi are kept in closed systems with biological filters in which the water circulates. This makes continuous dosing with fresh water very difficult. Because the various viruses, including “Herpes” is such a big problem, “DuPont Animal Health Solutions” in collaboration with Biosecurity sought a solution. A system has been developed, which will give good water condition under normal conditions. This without reducing the performance of the biological filters or increasing the concentration of Virkon to toxic levels. Virkon is primarily a powerful virucidal disinfectant for disinfecting aquatic material. It is effectively used in Koi ponds to purify the water of various viruses, including ‘Herpes’

Purifying the water of Koi ponds with Virkon® S

Most Koi ponds are equipped with a water pump, a microbiological filter and a UV light source. For dosing, however, UV and/or Ozone equipment should be switched off. After dosing, once Virkon has dispersed in the pond water, UV and/or Ozone can be turned back on. Ensure that the circulation pump(s) is/are actually in operation, during distribution of Virkon.

Dosage/use: Mix Virkon® S preferably in a bucket of water and distribute it evenly over the pond/quarantine. For dosing, UV and/or Ozone equipment should be switched off. Na het doseren, zodra Virkon zich in het vijverwater heeft verspreid, kan UV en/of Ozon weer worden ingeschakeld.

We at House Of Kata add an important parameter to “Measuring is Knowing”.
For years, we have been measuring common water values like Ammonium, Ammonia, Nitrite and Nitrate. We at House Of Kata add an important parameter Bacteria pressure. It has been found that pathogenic bacteria settle in the walls, soil, corners and pipes don’t be surprised beware of this silent killer.

Dosage Table:

Avoid contact with eyes and skin, In case of contact with eyes rinse with water and seek medical advice, Wear protective clothing and gloves, Keep out of reach of children, Store in a dry and cool place, Pot and any residues are subject to chemical waste.

How Virkon® S works
Virkon is a unique patented formulation based on a complex oxidising system in which a number of biocides are simultaneously effective on the physical (and chemical) components of a pathogen. The addition of a surfactant increases permeability, the presence of a buffer stabilises the low PH and optimises disinfection. Works on organic soiling and is temperature insensitive.

Suspected Disease Conditions
When there is a suspicion of Koi Herpes Virus (KHV) infection or “Spring Viraemia Virus” infection among a population of Koi, the obviously affected fish should be removed immediately. A specialist vet should be consulted at this stage. The water of the remaining healthy fish should be purified immediately with a dosage of 5 grams per 1,000 litres of water. (See dosage schedule) At this level of purification, it is essential that at least 10% of the water is changed weekly. Major concern and point of attention is that stress situations in the fish should be avoided at all costs. If these fish seem to remain healthy, water purification can be reduced and tapered in terms of both dosage and frequency. Obviously sick fish should however be removed as described above. REMEMBER that Virkon does not treat fish, IT IS NOT A MEDICINE! It only purifies the water to reduce infectious virus levels in the water. It therefore makes NO sense to treat fish with Virkon via an immersion bath.

Effects on biological filters
Virkon® S, by its nature, will kill off bacteria. So this will have some effect on biological filters. However, at a routine weekly maintenance dosage and provided that 5-10% of the pond water is changed before adding a new dosage, this should not affect the effectiveness of the biological filter. If a higher dose will be used and/or a higher frequency of dosing, some foaming may develop. This is not dangerous. The lipophilic surfactant (fat-loving/hydrophobic) that causes this is essential as part of its anti-viral activity. If foaming occurs AND this is perceived as a problem, a lower dose can be applied accompanied by increased water changes until no more foam forms on the water. Due to the great diversity in existing Koi filter and pond systems and water chemistry, no responsibility can be taken for any effect on fish or filter systems

Users (Koi keepers) have found that a good indicator of using Virkon at the right level is that the water in the pond shows a clean and slightly crystal-clear appearance. This can be a useful indication but this effect may not necessarily occur in all pond systems. It is possible to have a water test done through your dealer, which gives a good indication of the bacterial pressure in YOUR situation, in your pond. For more information, consult the supplier’s website and/or consult your dealer.

Despite the wide experience of safe use of Virkon, due to the great diversity in pond systems, no responsibility can be taken for any loss associated with the use of Virkon. Note; a disease like “Spring Viraemia of Carp” or “KHV” has a reporting requirement in many countries, either to your vet or competent authority. Also if you have suspicions that you have this disease.