Columnaris Information and Symptoms

Columnaris Information and Symptoms

By Rachel Hunt (Mushi)

Image © Danelle Columnaris is commonly mistaken for a fungal problem, it is NOT a fungus, it is caused by Flexibacter bacteria. Columnaris can be particularly difficult to diagnose as there are many symptoms associated with it.

Symptoms can include:

White, gray or clear stringy-looking "fungus" hanging off the betta's body or fins. Again, this is not actually fungus, but the Flexibacter bacteria. White or gray patches that look like mold or a slime covering, usually on the body (and most commonly around the dorsal area). White "pimples," generally around the chin and mouth area. White or gray tufts of "fungus" (often looks like cotton candy) anywhere on the body, but especially around the mouth, gills, or edges of scales. Lesions anywhere on the body, generally beginning in the dorsal area. Redness and swelling are not uncommon. In the later stages of infection, the bacteria will begin to eat away at the fish's scales, often leaving behind a red or brown looking bloody area surrounded by fungusy-looking tufts of bacteria. The Betta may also have clear, stringy feces and may be lacking appetite.

Columnaris is highly contagious. Any fish in a community setting showing signs of Columnaris should be removed to a hospital tank and treated seperately. A watchful eye should be kept on the fish remaining in the community for signs that they may be developing the disease.