It is pretty contagious and a tank wipe-out can be quick, so give some attention to the fry. Now! :)

I don't understand why the Melafix helps with skin ailments, but it does seem to aid the fish's immune system. As with all medicinal items, DON"T leave it in the tank after the treatment period.

By the way, "Flexibacter columnaris" is now (with the gender change in Latin) "Flavobacterium columnare" some places on the google search. You probably encountered that. :)

Maybe just Monday grumpiness, but with all the exposure of commercial fishes to columnaris, heximeta type infections and camallanus, I'm beginning to be amazed that anyone stays in the hobby beyond six months!

Shops are in a pickle. If they quarantine and medicate new fishes, they must charge a lot more. Customers go elsewhere.

Ironically, after deaths, one may be paying a lot more for their fish than if they purchased from a quarantining outfit. American aquarists have a somewhat deserved reputation, compared to relatively high rolling German or Japanese aquarists, of being cheapskates. Many of the rarer fish go to Germany or Japan because someone (in the higher paid classes?) will pay a premium price.

If Americans would pay more, the wholesalers (a logical intermediate point between fish farms, collectors and local breeders) could preventatively treat and hold fish. I don't know how to get that started.

(Recall a recent story of a lady upset about the dollar a neon price. She claimed to have bought 10 for $4.00 just the week before. Of course only one survived. My informant brought her attention to that, "That was a pretty expensive neon." She just looked puzzeled and blinked.)

In the short term, shops make more money on the person who kills fish and is back every two weeks. That is short sighted though, because those people will be gone in a few months and  the tank will be in a garage sale next spring. (Always, bleach what you can that was purchased at garage sales.)

The veteran pet shop customer certainly will not dump as much cash per year. But long term pet owners should be good for a couple $100 a year for a decade or more if they stay in the hobby. They also are useful in chatting with newbies in the shops and - oh yeah - on Net forums. ;)

Rant mode off.