Koi Health and Supplies » Parasite Treatments

Proper treatment for parasites depends on which parasite the koi have. If you have access to a microscope, by simply taking a scraping from the fish and examining it under the microscope, you can usually tell exactly which parasites are present and then treat for them accordingly.

There are some links below for video of what these parasites look like at 100x magnification.

Supaverm is safe for use on koi only. It will kill goldfish! It is believed to remain in the water after use for up to one month. It will not harm the filter media. Remember to shake the bottle well before use. Treat the pond with 1 ml per 100 gallons. Do not perform any water changes for at least 10 days. Supaverm has been shown to be much more effective when used with a salt level of .3% or higher. For that reason we highly recommend using it with salt. If there are plants in the pond and the use of salt is not possible, we recommend treating a second time 5 days later. It is not necessary to do a water change after using Supaverm.

Malachite Green & Formalin should not be used when the salt level in the pond is higher than .1% unless you know for a fact that the pond water is very soft. If the pond water is hard at all and the salt level is above .1%, the use of formalin can severely burn the gills of the koi. Malachite Green & Formalin can kill the beneficial bacteria in the biological filter, so if possible, the filter should be bypassed for at least 8 hours during use. Malachite Green & Formalin can kill plants so, if possible, all plants should be removed while the pond is being treated and the plants should be treated with potassium permanganate separately before returned to the pond. (To treat pond plants for parasites, mix up a solution of 3 tablespoons of potassium permanganate dissolved in 12 gallons of water. Allow the plants root ball to dry out slightly and then completely submerge the plant root system in the solution for 2 hours.)

• To treat ponds up to 1500 gallons. Measure out enough Malachite Green & Formalin to treat the whole pond at a dosage of 10 ml per 100 gallons. Drain 50% of the water out of the pond and then add the Malachite Green & Formalin to the pond. After exactly 2 hours, refill the pond as fast as possible to its normal level. You must be able to refill the pond within 45 minutes or you risk the chance of burning the fishes gills. Perform this treatment 3 days in a row. If you have costia we recommend treating one more time on day 5. If the pond is being refilled with city water remember to add dechlorinator to the water to remove any chlorine in the new water. This technique is very effective because the parasites are exposed to twice the dose of medication for 2 hours which is usually enough to kill them.
• To treat ponds over 1500 gallons. The above treatment cannot usually be performed on ponds over 1500 gallons because it takes too long to refill the larger ponds. In this case we recommend performing a 25% water change before each treatment. After the pond is refilled to its normal level, add the Malachite Green & Formalin at a dose of 10 ml per 100 gallons. Treat the pond 3 days in a row. If you have costia we recommend treating one more time on day 5. If the pond is being refilled with city water remember to add dechlorinator to the water to remove any chlorine in the new water.
  

Salt when used to treat for ich should be added at a rate of 1 pound per 100 gallons of water each day until the pond reaches .4% salt. If there is no salt in the pond to start with, this will take 4 days to reach .4%. A 1000 gallon pond will require 40 pounds of salt to reach a salt level of .4%. This may sound like a lot of salt but if you add it over a 4 day period it will not bother the fish or the filter. Leave the salt level at .4% for at least 3 weeks. Ich is easily killed with salt when it come out from under the fish's scale to reproduce, however it's life cycle is such that it could take up to 3 weeks to come out and be exposed to the salt water. You can purchase 50 pound bags of solar salt at Home Depot for around $5.00 each. Use the cheapest salt you can find because it will have no additives in it which could be harmful to the koi.

Optional Treatment-Potassium Permanganate. A very effective alternative to Malichite Green & Formalin which many people have had very good success with is Potassium Permanganate, but it is much more dangerous than Malichite Green & Formalin and is more complicated to use. Potassium Permanganate is an oxidizing agent which means, that to kill the parasites it must first oxidize most, if not all, of the organic material in the pond. For that reason it is hard to recommend a proper dose for a pond unless you know how much organic matter is in the pond. The proper starting dose for a pond that is very dirty will kill the fish in a pond that is extremely clean. The end results that you are trying to achieve is to have the level of oxidation in the pond high enough and for a long enough period of time to kill the parasites, without killing the fish. This is not really easy, but it can be done very successfully if you pay attention to what you are doing. The following is the technique that we have tried and found to be successful:

• Remove all plants from the pond.
• Remove as much leaves or debris from the pond bottom as possible.
• Empty all skimmer baskets.
• Turn off ultraviolet light.
• Bypass the biological filter. If you cannot bypass your biological filter, do not use this process. Potassium Permanganate will kill all the good bacteria in your filter, which will cause serious water quality problems.
• Sunlight tends to break down Potassium Permanganate, so if you can begin the treatment after the direct sunlight is off the pond it can be helpful.
• The standard initial treatment dose is 1 level teaspoon per 600 gallons of pond water. If the pond is extremely dirty you can increase this dose by 25%. If the pond is brand new and has very little algae growth, you might reduce the dose by 25%.
• Potassium Permanganate is very toxic. Do not breathe it or get it on your skin.
• Salt pond to .3%
• Have some Hydrogen Peroxide on hand in case you need to neutralize it. You can find it in most grocery or drug stores
  

Potassium permanganate treatment. Potassium permanganate consumes large quantities of oxygen during the treatment so make sure the pump to the waterfall is running at all times and add some air stones if you suspect the oxygen level may be low. When potassium permanganate is added to the water it will turn the pond a bright purple at first and then a "Pink Champagne". As long as the water is a "Pink Champagne" color it is active and is oxidizing any organic mater in the pond including parasites. When it turns to a yellow "Tea" color is has been used up and is no longer oxidizing anything. By scooping up a sample of the water in a white ceramic or plastic cup it will makes it much easier to tell when the water changes color.

• Day 1- Add the proper dose of potassium permanganate to the pond. Note the time it takes to change color. As soon as it changes to a tea color you can stop bypassing the filter.
• Day 2- Add the proper dose of potassium permanganate to the pond. Note the time it takes to change color. As soon as it changes to a tea color you can stop bypassing the filter.
• Continue to treat the pond each day until the pond stays pink for at least 8 hours at one time. Skip one day and then treat the pond one more time except reduce the dose of potassium permanganate by 20%. After the pond has stayed pink for the second 8 hour period, neutralize the pond with Hydrogen Peroxide at a rate of approximately one quart for every 2,000 gallons. Within 30 minutes the water should be very clear. Perform a 40% water change and you should have parasite free fish swimming in very clean water. The only exception may be ich. If you suspect ich you should replace the salt lost durring the water change and maintain it for an additional 10 days. Do not forget to add dechlorinator to the new water.
  

Note: If at anytime during the treatment the water gets so cloudy that you cannot see your fish and you get concerned, you can neutralize the potassium permanganate and make the water clear by adding Hydrogen Peroxide, but if you choose to add Hydrogen Peroxide at anytime during the treatment you will need to wait 3 full days for the Hydrogen Peroxide to evaporate before you restart the treatment.

What if you do not know what parasites your koi may have?

The following is a treatment procedure that we use at Sacramento Koi every time we get new koi. This procedure is designed to kill all five parasites in case they are present.

Day 1 Treat the pond with Malachite Green & Formalin
Day 2 Second treatment of Malachite Green & Formalin
Day 3 Third treatment of Malachite Green & Formalin
Day 4 Forth treatment of Malachite Green & Formalin
Day 5 Fifth treatment of Malachite Green & Formalin
Day 6 25% Water Change
Day 7 Add salt to increase pond salt level to .1%
Day 8 Add salt to increase pond salt level to .2%
Day 9 Add salt to increase pond salt level to .3% and add full dose of Supaverm
Day 10 Add salt to increase pond salt level to .4%
Day 14 Add a second full dose of Supaverm
Day 23 the koi should be totally parasite free.

Click on the link below for a black copy of this Treatment Schedual.