Potassium Permanganate Dip.
This treatment is very hard on fish, and is only for external problems. Please do not use it unless you are absolutely sure that the fish you need to treat really needs this treatment, and there is absolutely no other less traumatic means of treating the fish for its problems). This treatment can kill your valuable fish. Be warned!
Now you’ve had the warning. I can continue with what I’ve learned.
This treatment will kill external parasites like flukes (incl. gill flukes) and just about any pathogen/bacteria on a fish that may be causing it problems. This treatment will also remove the slime coat from your Discus, and leave it unprotected during the time it takes for the fish to re-grow its slime coat. A similar treatment with a 3-minute dip (for adult fish) has been recommended by Jim Quarles and others as a treatment for ‘The Discus Plague’
Prepare a sterile tank and add 1 tblsp of none iodized salt per 10 gals and an air stone. Prepare (clean) and fill two buckets (or similar containers). Try to make sure the water in the tank and buckets (containers) has the same or similar parameters as that from which the fish are to be taken. To one bucket (container), add 10mls of base mix per gal (4 ltrs) of water and give it a stir. The water will be a very dark purple. (almost black). Net the fish, and using a stopwatch or other accurate time measuring device, dip the net and fish into the container of PP mix for 1.5 minutes. Remove the fish (still in the net) and immediately dip it (and net) in the other clean prepared bucket to rinse, and then place the fish into the clean tank to recover from its ordeal. The fish should completely re-grow/replace its slime coat within 12 hrs or so. Following this treatment, the fish should be quarantined for at least 4 weeks to ascertain that the problems have been removed, and the fish is well enough to be returned to its normal habitat.. I can only add that I hope you never have to use this procedure.
All the best, teddy,j