Discus Plaque

Discus Plaque


By Jim E. Quarles

What is this thing called discus plague? Were does it come from? Do my fish have it? If they do how do I cure or treat it? Will the same fish get it again?

All the above questions come rushing to your mind when you first think your fish are infested with this disease. You worry you will lose all the fish because this Plague when if first appeared in the United States generally wiped out entire populations of both Angelfish and Discus in hatcheries across the entire U.S. and Canada.

Like most new forms of disease this one hit with a bang. Little was known about it. Most hobbyists and even professional breeders were caught flat footed by this new problem.

First let me state clearly I am not a fish pathologist. The only thing I really can speak to is my personal experience with this disease. So bear in mind what I have to offer is nothing but one man's personal results and method for dealing with the DISCUS PLAGUE.

About five or six years ago I was hit in the discus hatchery for the first time by what is commonly called discus plague. It was not a fun event let me tell you! For those of you who have not had it or seen it I think it best to describe what it looks like at its onset in the fish.

The first thing I noticed was a general darkening of the fish, they started showing signs of stress. They would hide if possible, or go to the bottom of the tank and remain there. Some would lay on their sides somewhat.

Then in a few hours I noticed a problem with the slim coat developing, it looked like pealing snot on some areas of the skin. At that time a sickening odor of decay was noticed coming from the tank. Massive water changes helped with the stress somewhat but did not reduce the progress of the disease much. If it is really discus plague you will notice that the area under the pectoral fins will remain pretty much clear of the peeling of the slime coat.

With time the fish will lose all interest in feeding. Then other effects of disease start to appear. Fin rot is noticed as the fin edges turn whitish and become ragged. As this progresses you will lose a lot of the fin to rot.

This is I believe, a secondary infection of a different disease, so now you you have at least two diseases working at the same time, both are external parasites or bacteria thank goodness and will respond to treatment.

If treatment is not started quickly another disease factor may come in to complicate the problem even more. Columnaris is likely to come into the picture at this point. These factors are why the plague is a wipe out disease.

What starts the process? Who knows for sure, I have seen dozens of ideas expounded some sound good others are silly. But none of that matters as long as you can treat and cure the problems.


First let me state that a lot of people confuse Columnaris with true discus plague, also some do the same thing when they have advanced Fin Rot. If you think you have discus plague, it is a judgement call as to what the true disease is with your fish.

While there are different treatments for the control of Columnaris and Fin Rot, the same treatment for Plague will cure them as well. I have tried just about all the suggested cures or treatments, some work fairly well but take to long, others don't work at all and the fish die. I would be the last to tell you that any one method is proven to be better than others. Yet I prefer the one I developed and has become the rave to some who would use it to cure discus hang nail, which was never my intent for it.

My treatment involves the careful use of Potassium Permanganate Powder.

Warning this is a powerful chemical and if not used properly can damage or kill your fish as well as blind you if you get it in your eyes. So great care when using it is called for. This product will also stain your skin and anything you may be wearing at the time of it's use. Be careful.

In my book "Success With Discus Vol.1. On page 62 you will find the treatment detailed below.

I mix 1/8 teaspoon of potassium permanganate powder with one pint of water. I then pour this mixture into a 20 gallon thank which is empty of everything other then water at 86 degrees and an air stone turned on full air supply. After the mixture is added, I catch one or two diseased fish in a rather large soft net. The fish remain in the net and are dipped in the tank for no more then three minutes. For half grown fish I would cut the time to two minutes. I would never use this treatment of any discus less then 3 inches in total size.

Once the fish have been in the net in the mixture for the required time span I transfer them to a clean tank, that has not been infected. It does little good if any at all to do the dip and return the fish to an infected tank.

I proceed to treat all the infected fish with this method until all the fish have been dipped and placed in clean tanks.

I then add one teaspoon of rock salt to each five gallons of water in the new tanks. In addition I also add one drop per gallon of Malachite green zinc free.

If you would prefer you can leave out the Malachite green and replace with 1/4 teaspoon of Gentamicin Powder to each 20 gallons of water.

Then wait at least 24 hours and check the results on the slime coat. If it still shows signs of peeling a whitish slime you can repeat the treatment using fresh mixture of P.P. I would reduce the time on any second treatment to 2 minutes in the dip bath. Once again return the fish to a clean fresh new tank.

Do not return them to an infected tank. This is a very effective treatment for Discus Plague along with the other diseases that generally develop with it.

It has no lasting effect on the fish, and they will return to normal health and their spawning efforts will not be involved.

One interesting note. Once the fish have been cured once, the same fish will never again be subject to discus plague. Other diseases perhaps but not the plague.

Timing in the dip is very important, do not go beyond the max time in the dip of more then three minutes. If you do, your fish will suffer gill damage and may die.

Use this treatment at your own risk. I know it works but can not warranty your application of it.

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