Flavobacterium columnare
Hi Tug,
Most of us learn things the hard way; I learned the lesson then had to relearn it, kind of like being held back a year.
The eighth-grade was the best five years of my life!
Based on what you described, assuming you saw “white fuzz” on the critter. The condition known as Columnaris, your conclusion regarding the bad-guy is probably correct, though archaically named, the “modern” name is Flavobacterium columnare, and as with most bad-guy, bacterium is Gram-negative. Since it is, Gram-negative Erythromycin (Maracyn) should work. Though the preferred (I think) medication is food containing Oxytetracycline, as long as the fish is still eating. :gw
The real danger is Columnaris in the gills; this is where the fish exhibits rapid and usually distressed breathing. The gills will appear brown or light brown; you may observe the “white fuzz” on or in the gills. If you sedate and look closely you will probably observe dead (necrotic) gill tissue.
Flavobacterium columnare is an “ambush” or opportunistic bug, meaning it only strikes damaged or weakened fish. It is a true scourge of the aquaculture community. High bio-loads, jostling, handling, poor water conditions and so forth are where this little nasty strikes.
The reason quarantine is so effective is that most of our critters face, most of the aforementioned conditions on their way to us. A couple of weeks in a nice clean well aerated Sterilite container, stuck out of the traffic pattern and not having to fend for itself in a new environment with established residents can make all the difference.
Quarantine is so effective that after years of not seeing a sick fish, it is easy to become complacent. The reality is that the illnesses and injuries were cured, the wounds healed by that short time out.
Many who admit not quarantining will insist that it has never made a difference, I challenge people to look at their receipts and account for your fish, most folks have what I would consider an alarming mortality rate, especially within the first month of ownership.
Quarantine/hospital tank is equally effective for current inmates, an injured fish or even one that is just out of sorts are often revived with a little “time-out.”
Having said all of this, you really can over do the medicating. Having a little malachite green, methylene blue and Potassium Permanganate on hand is a good idea.
I use Nitrofuracin Green for all fish I ship and sometimes in quarantine, especially for wild caught fish that have not spent much time with someone I trust. By the way I quarantine everybody, I even quarantine moving fish from one area to the other. :gw
Good luck (and quarantine),
Biollante