In light of the recent posts, and all the misinformation on the web and floating around in this forum, let me set a few records straight.
Mycos is nothing to be considered lightly. I have been in regular conversation with fish pathologists for almost a year now, and it is a very serious disease and in most of the fish available at your local pet shop. Their guess is 70% of the TRADE. That means ALL fish. You need to read the article I have created at the link below, and take it very serious, as it is based on the research of people that look at mycos for a living:
I have friends that have dealt or are dealing with this. FROM ONE FREAKING FISH I destroyed 3 years of work, over 500 bettas in one afternoon. I could not even enter my fish room for days. I dealt with fin rot, lesions, lifted gill plates, dropsy and the list goes on. I finally contacted a fish pathologist and sent THIRTY fish representing every tank or system I had. The ones with lesions tested positive for mycos right off the lesions they presented.
ALL were diced up and tested and ALL tested positive for mycos. Fish from 30 days to 9 months of age. It was recommended I send more fish to the leading researcher in mycobacteria here in the US to determine the strain. They were unable to grow the bacteria to determine what strain I was dealing with and was told that is not unusual for many mycos strains. It took DNA to determine what I had. My results and currently what many betta breeders are dealing with is M. Triplex. Thats right.. something you have NOT heard of. Google it. And you will find it shows up in people.
If you read the article I posted you will see there are different types of mycos. Some move fast and others a bit slower. But the end result is THERE IS NO CURE and THE FISH WILL DIE. Some mycos can be managed as there is no way to completely eradicate it. But you destroy the pathogenic ones and manage water conditions to reduce affect of the others.
I was told Lysol will kill it. Not knowing there were different Lysols I ran a major heavy solution through my barracks for TWO WEEKS. I drained that down, ran water through it a few days, drained it down and ran a super concentrated bleach solution through another TWO WEEKS. I brought the system back online and put some of my most promising fish in the barracks and EACH ONE CAME DOWN WITH THE DISEASE AGAIN! The ones still in the tank never got it. So DO NOT tell me you can bleach or use vinegar on this. DO NOT tell me it is not that serious.
So once again I have had to destroy some absolutely beautiful fish. More discussion with the pathologists and we found I did not use a proper cleaner. I sure as heck do now. EVERYTHING.., nets, hoses, tanks, lights water test vials.. EVERYTHING gets hit with the anti TB chemical after EVERY use. My trash cans for water are broken down and sprayed every few weeks. Even my hands between tanks. I set a timer as there has to be 5 minutes contact time. I refuse to destroy any more fish. I have clean stock now and I am going to keep it that way.
In the meantime. My recommendations.. for all it is worth..
Get a hold of a local vet or go online and get something that will kill TB. The article I linked to has a link to chemicals that will kill mycobacteria. Treat EVERYTHING in your fish room no matter how small. And treat any tank with it when you break it down... sick fish or not. Keep the stuff on hand and act like it is ever present to get a foothold in your fish room. Practice good bio-security and you should prevent it or get rid of it. If you have sick fish - destroy them, nuke everything and start fresh being more careful.