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garyroland actually inspired this series of articles, old timer that he is, with his frequent use of drugstore chemicals for the treatment of diseases over commercially available preparations found at the LFS. Great care should be taken when dosing any of these remedies, as reckless action with them is often disastrous. Make sure you know what you're doing and accept the risks before attempting any of these treatments.

I'm going to describe the use of potassium permanganate or "permanganate of potash" first, as I have seen it come up quite a few times on the boards recently without much explanation.

Potassium permanganate (KMnO4) is a powerful oxidizing agent that chemically "burns" any organic material it comes into contact with. Chemical treatments are never discriminating, so this "organic material" includes your skin and your fishes' tissue. You'll want to take great care when dosing this chemical, as an overdose will kill your fish; contact with it can cause burns, will stain anything it comes into contact with and inhaling the powdered crystal form can cause respiratory irritation. It's a good idea to wear gloves and eye protection when handling potassium permanganate to avoid any contact with skin and eyes. A dust mask can be worn to prevent inhalation. Potassium Permanganate should NEVER be mixed with Formalin, as the combination can be explosive.

Potassium Permanganate is most often used as a treatment for external parasites, true fungus or columnaris infection. The oxidating action of the chemical will essentially burn whatever organism you're trying to get rid of to death. I've personally had success using this application for the treatment of fish lice, but it will work for any EXTERNAL parasite, fungus or bacterial infection; potassium permanganate has been used in aquaculture for all of the above indications for many many years. It can also be dosed in extreme cases of algal infestation, but I won't be discussing this application here.

To prepare your tank before dosing potassium permanganate, you'll want to make sure the tank is fairly clean. Make sure your gravel doesn't have a lot of food buildup on it and do a partial water change to reduce dissolved organic compounds. A large amount of organic pollution in the tank will render this treatment ineffective, as the oxidating action of the chemical will be used up on the waste instead of the desired organism. The use of potassium permanganate WILL harm your biological filter, so it may be a good idea to remove your seeded filter media before dosing, along with any activated carbon.

Most of the time, you'll find potassium permanganate comercially in powder or crystal form, which should be dissolved in water before being dosed to the tank. For the treatment of external infections and parasites, the usual recommended dose is 2 ppm KMnO4 or 2 mg/L. You need to be very careful in determining the amount of chemical to use, as overdosing can be fatal. You'll need a scale to determine the required amount BY WEIGHT as this is the only reliable method. Dietary scales are inexpensive and can be purchased at pharmacies. They are invaluable and should be on hand for any aquarist that plans on dabbling in the use of chemical treatments.

Some fish are sensitive to the use of potassium permanganate and care should be exercised the first time you use it in any case. If fish seem distressed while using the chemical at 2 mg/L, the dose can be reduced to 1 mg/L to help with this problem. Be especially cautious when treating Malawi cichlids, chemically sensitive and scaleless fish. If your fish seem distressed while using the treatment, a partial water change with fresh water at the same pH and temperature as the tank should be used to prevent mortality.

There are two ways of measuring the dosage of potassium permanganate for use in aquariums and ponds. By far the easiest is to make a stock solution that can be used for multiple tanks and applications. All you need to do is purchase a 1 gallon bottle of distilled water, weigh out 285 grams of potassium permanganate and dissolve it in the distilled water. 1 drop of this solution per gallon will give you a 1 mg/L strength in the aquarium overall. So to get the required dosage of 2 mg/L in a 10 gallon aquarium, you'll need to add 20 drops. The stock solution can be kept in a cool, dark place for up to one year before it needs to be replaced.

There is also a formula to determine the amount of potassium permanganate needed to treat your aquarium by weight:

Grams of Chemical = Gallons Treated 0.0038 2 mg/L

By this method, you would calculate the amount of chemical needed for your aquarium using the formula, weigh that amount of potassium permanganate in grams, dissolve it in a small amount of tank water and add it to the aquarium. I highly recommend the first method, as it is much easier and has less risk of overdose.

Your fish should be exposed to the treatment for at least 4 hours. Your water will take on a purplish colour which should stay for the duration of the 4 hour treatment. If the water turns a murky brown colour during this time, the chemical has been "used up" by other organic material in the aquarium and the dose should be increased to 4 mg/L. Following treatment, a few drops of hydrogen peroxide can be added to the water to neutralize the potassium permanganate, following a large partial water change of about 30%. During treatment with potassium permanganate, surface agitation should be very aggressive as it can reduce the amount of dissolved oxygen available in the water. Also, care should be taken when using it in alkaline conditions as its toxicity is increased.

A 30 minute dip or bath can also be utilized at 10 mg/L, which is especially useful in the treatment of columnaris infection when followed with a small amount of aquarium salt added to the tank water. This is also the reccommended treatement for larger parsites such as gill flukes which may not respond to a weaker solution. Be sure to watch your fish during the bath to make sure it isn't getting too stressed, and make sure the surface of the water is well agitated. Potassium permanganate can also be used as a topical treatment at up to 200 mg/L but its use is not recommended as there are other chemicals which are much better suited to this purpose.

Potassium Permanganate treatment should only be used about once a week to prevent too much tissue and slime coat damage to the fish, so it's really not a good choice if it will need to be repeated for something like Ich.

I hope this article clears up some confusion regarding the use of this chemical. As I'm by no means an expert, I'm sure some veterans will step in and make any corrections as needed. Any treatment used is entirely at your own risk.

(Did she call me an "old timer"??)...

A good remedy for "itch", fish that seem to itch but never develope white spots is of course "Permanganate of Potash".

Numerous organisms in the water cause the "itch".

The dose is 1/8th grain to the gallon for 2 hours. After that, syphon the bottom of the tank (gravel) drawing off half of the water and replace with new same temp and pH water.

The Permanganate will clear by itself.

If "Light-Bright" is tuned in she can also dose this product, same strength and procedure, to kill algae.

--garyroland.

[span class="edited"][Edited by garyroland 2004-08-29 19:18][/span]

Very informative, thanks trystianity. It's much nicer than other drug store items I've used, and does not warrant strange looks. ( Fleet Enema is a great source of phosphates for dosing your planted tank with, but if you buy more than one at a time....well, you can imagine the looks as you buy 8 or more enemas, lol).

I was going to ask why the disolved oxygen is reduced... but then recalled the combination of the peroxide and potasium permanganate produces hydrogen as a by-product of the reaction. Obviously, the free hydrogen passing through the water can potentially disolve, and form the base for hydrochloric acid(reating with disolve chlorides in the water...), which would alter your pH.Hmmm.. i hate it when i answer my own question

Thanks for taking the time to write all that out tryst. Over here in Oz its very difficult to get effective medications for our fish so to have this sort of knowledge is very valuable to us. (well I think so anyway!)

---

Before you criticize someone walk a mile in their shoes. That way you're a mile away and you have their shoes.

Thanks for the replies.

Now I just have to figure out which treatment I'll be trying to write up next. Epsom salt baths might be fun, but not nearly as informative.

jake, the thought of you going into a drugstore to purchase 8 enemas is just hilarious!

Hehe, and looking at the face of the cashier when I explain what they're for is pretty funny also.

" You're what??!?! An enema for your aquarium!??"

Somewhere in their heads they believe I'm going to administer enemas to my fish, and I can't tell them any different.

I've recently switched to powdered mono potassium phosphate...just wasn't worth it anymore, lol.