Originally Posted by clinton1621

Ok, from researching several different sources, some mentioning a few symptoms and others listing full symptoms, here is a rough workup for possible diagnosis by symptoms.....

1. Early stages present possibly on the glass as small white clearish looking strings (resembles a parasite but really small) that flow in the water current.

2. Small white to gray 'pimples' or spots on the fishes lips, gill plates, body, or fins that have a stringy look to them (note that ich appears similar but is much smaller and does not appear stringy).... this is an early stage of columnaris and is harder to spot. Other possible symptoms at this stage could be flashing, darting around erraticly, scratching, or shimmying. Lack of appetite may not be noticed at this stage, so just because they are still eating doesnt mean they are healthy.

3. Spreading of the pimples or spots to a larger size and noticable loss of flesh and coloring in the surrounding tissue, usually inflamed as well. This stage leads to multiple infections of other diseases or parasites (most commonly fungal infections, which is why they are often confused in diagnosis) due to the open sores as the columnaris decays the tissue. Probable notice of lack of appetite.

4. Gill infestation which turns the gills a brown to black color, this is much harder to see and by this point it is rarely treatable as the columaris will have destroyed enough gill tissue to make it irreversable. Rapid gilling and lack of movement and appetite are very likely.

5. In the later EXTERNAL stages such as #'s 3. and 4. above (which should be obvious by then) the fish will stop eating entirely and become lethargic. Massive loss of tissue and severe necrosis down to the internal organs is possible. This stage is also rarely treatable as the damage to the fish is too severe. Note that internal infections will also cause them to stop eating completely as well, but there may be NO external signs on the fish, so this would be a much harder diagnosis.

6. Internal infections as mentioned in # 5. above sometimes present no external symptoms, this causes muscle tissue loss and organ necrosis from the inside out. For obvious reasons this is very hard to diagnose and usually by the time it presents externally it is too late for treatment to be succesful.

7. This is a tough one... certain strains will kill the fish in as little as 24 to 48 hours with possibly none of the symptoms listed above. Usually a tank wide die off occurs without warning over the course of a few days. This strain is virtually untreatable.


Treatment....

Lower the water temp to 75 - 76 degrees... higher temps make this bacteria multiply faster and become more agressive.

Raise oxygen levels in the tank... lower oxygen levels do the same as high temps, and the fish will also need the extra oxygen in case of gill damage.

Gram Negative antibacterials such as,

Triple Sulfa or any gram negative Sulfa meds will work in the very early stages.

Kanamycin, Nitrofurazone or Minocycline (Maracyn 2) will work in either early or later stages.

There are also medicated foods , such as oxytetracycline, that are listed as possible treatments but due to the fact that the fish usually arent eating I would say these would only be effective in VERY early stages

Note that gram positive Tetracycline and Erythromicin (Maracyn 1) are sometimes listed as treatments, but they are NOT EFFECTIVE because columnaris is gram negative.

EDIT : This bacteria is highly attracted to the fishes organic slime coat and is why it also can appear on the inside glass surface where there is a buildup of organic slime.