This link is taken from one of the best columnaris links;
POTASSIUM PERMANGANATE KMnO4:
The permanganate ion is a strong oxidizing agent.
Potassium Permanganate is a strong oxidizer that when added to water will give a deep purple color that will slowly turn brown/yellow as it oxidizes. The more dissolved organics, the more quickly the change of color to brown/yellow which indicates the oxidation properties are mostly spent.
USE:
- Being an oxidizer, Potassium Permanganate is useful for water clarification and odor elimination; often where a bacterial cloud is present.
Potassium Permanganate should only be used in established cycled aquariums.
Potassium Permanganate can be used to reduce dangerous high organic levels in freshwater ponds and aquariums, especially “Bacterial Blooms” (Grey cloudy tanks).
It can be used as a special-purpose freshwater conditioner for ponds and aquariums, because of its ability to improve water quality by oxidation of excessive dissolved and suspended organics. The chronic presence of excessive dissolved organics in the water promotes the growth of potential disease-causing bacteria such as Aeromonas, and as well lower KH and pH.
However it should be noted that initial oxidation produces Carbon Dioxide which will initially lower pH/KH and I recommend a water change a day after the use of Potassium Permanganate for the purpose of oxidation of organics in ponds or aquariums.
- Probably the best use for Potassium Permanganate is for fish baths or swabbing infections caused by bacterium such as Columnaris.
For these uses, a fish keeper would use in a bath at double recommended tank strength for 30 minutes.
Product Resource: Potassium Permanganate
Do NOT combine with Methylene Blue in baths.
MB is a better choice where stress has occurred or ammonia and nitrite poisoning has occurred. Whereas Potassium Permanganate is the better choice for Flukes, external nematodes, Anchor worms, Columnaris or Aeromonas/Vibrio infections.
HOWEVER, even the use for Columnaris and the other before mentioned "diseases', it should be noted that is the fish are weakened severely or if the fish is very sensitive fish (such as scaleless fish like Knife fish), Methylene Blue may still be the better choice even if less effective, as the oxidizing properties of Potassium Permanganate may be too much for these fish (1/2 strength may be another option).
Please see this article for more about fish baths/dips:
“How to Perform a Medicated Fish Bath or Dip”
- Potassium Permanganate can be used as a plant dip for snails at double recommended tank strength for 10 -20 minutes. In the tank it can be used for Fluke treatment and is mildly effective for snail eradication (not a recommended snail removal method from my experience).
- Potassium Permanganate is the best choice for a net dip, as it is both effective, yet not nearly as dangerous as other effective alternatives such as bleach if some accidentally finds its way into the aquarium.
A second quick dip in water containing any chlorine removing water conditioner such as Start Right or Prime is suggested (not 100% required) to remove excess PP prior to use in the aquarium.
- Potassium Permanganate is also an excellent “second choice” for direct (full strength) application to fish eye infections (cloudy eyes, “Fish Cataracts”).
Hospital tank treatment with Erythromycin is also recommended.
Silver Nitrate is the first choice for eye problems, however this product is nearly impossible to find and requires special handling and should be followed by Potassium Dichromate. The strong oxidizing properties of Potassium Permanganate makes it useful for some serious wounds where you want to “seal” the wound, such as a fish with a missing eye, but do NOT use on open 'bloody' wounds.
- Another use is for mild Fluke (Trematode) infestations.
Reference: “Trematodes & Nematodes in Fish”)
If preparing your own (dry) Potassium Permanganate treatment, use 2 ppm per liter of water for in tank (pond) treatments and up to 10 ppm per liter for 10 -30 minute baths.
For already prepared Potassium Permanganate (in liquid form) such as Jungle's Clear Water, use double the recommended normal tank dosage for a bath.
Product Source:
Jungle Clear Water
Care must be exercised when using this product, whatever level dosage is used. The action of Potassium Permanganate proceed more rapidly under acidic water conditions and higher temperatures, while the action is less rapid at higher pH and water hardness.
Also do not combine with de-chlorinators as these products are reducers (usually container Sodium Thiosulfate or other reducers) that will immediately remove Potassium Permanganate since it is an oxidizer.
Please keep in mind that this is an oxidizer than can and will destroy beneficial bacteria, so use with care if you must treat a main display tank (which is why I prefer baths or hospital tanks).
An aquarist/Pond Keeper should also note that Potassium Permanganate suppresses photosynthesis in plants in the water, although this can be beneficial, especially in ponds with large amounts of decomposing organics as this will increase oxygen levels in the pond, particularly at night. In this process Potassium Permanganate reduces biological oxygen demand, and improves water quality and clarity.
In case of accidental overdose with Potassium Permanganate, a 2 to 3x dose of Prime in the tank will immediately remove this, or if a fish reacts adversely after swabbing a sore, lesion, etc. an immediate dip into water treated with Prime (or similar water conditioners such as Start Right, Amquel, Stress Coat, etc.) at 3 x strength will immediately stop the reaction.
