Previously known as Myxobacterial Disease, Columnaris is a bacterial disease. Initially, it presents like cotton wool, commonly around the gills, mouth and skin of freshwater fish.
Columnaris is primarily an epithelial disease. Meaning that its attack will most likely be formed on the exterior of a fish. It causes erosive lesions on the skin and gills that may become systemic (internal).
The most common member of this group is known as Flavobacterium columnare and has affected freshwater fish on a worldwide scale.
Columnaris is a highly transmittable disease/infection and can wipe out an entire community of freshwater fish within a few hours to a few days depending on the temperature. It is usually pathogenic at temperatures higher than -15 degrees C (59F). Mortality and acuteness of this disease increase as the temperature does.
An example from the book of Noga explains:
“experimental infections can kill oriental weatherfish within -7days at -15 degrees C (59F) and in only 1 day at 35 degrees C (95F)”
This information indicates that, if we have noticed Columnaris disease in our tanks, the immediate action that is required is to try as safely as possible to drop the temperature as much as we can. Only this will buy us time to find the meds required to treat the disease from spreading and keeping the mortality rate down. Any tools used such as siphons, nets, ornaments, gravel etc etc will need to be sterilized. If any of this equipment has come into contact with other community tanks, then ALL the fish will need to be immediately treated.
Studies have supported that Columnaris as a disease and its infection begins with poor quality of water. Uneaten foods, fish waste not removed, high nitrates and hard water as well as the biological filter media not being cleaned regularly enough. Other factors may include low oxygen levels in the water, physical injuries left unattended in a badly maintained aquarium etc... In a well established aquarium, after many years, should an outbreak of Columnaris occur, it is most likely due to bad maintenance of the aquarium and its filtration media, meaning, it will affect the entire community of fish. Tropical fish are not exempt from an outbreak of Columnaris disease.
So, what to look for?
if your fish has a few areas on its body that present as a whitish appearance, which resemble the look of cotton wool in the areas of Gills, Mouth or Skin (can even cause scales to pop out or fall off at different locations (not pineconed) ). White spots on the skin beginning to look ulcerated and fluffy that may be turning yellow (mucus like) with/or beginning to form a red ring around the outside of the ulcer (advanced stages), lethargy, possible sudden weightloss/anorexia, then it is most likely Columnaris Disease and you need to act very fast.
The change of colour to the lesions indicates bacteria are growing rapidly. Begins white, changes colour to yellow and then to orange as the bacterium matures.
How to treat:
Treatment requires highly toxic and aggressive medications that we, under normal circumstances refrain from suggesting their use here on kokos because of their potential damage to gills and organs, under normal circumstances we practice safer treatment methods. however, due to the aggressive nature of this disease, and in the advice from the experts that contributed to the book of Noga, here is how and what they recommend as treatment for Columnaris Disease:
For surface infections only:
For Systemic infection:
if ulcers are showing on 5% or over of body surface area indicating advanced cases, then an appropriate antibiotic needs to be used.
Noga suggests “Oxytetracycline and/or nifurpirinol, but not many if not all are resistant to ormetoprim-sulfadimethoxine and other sulfas”
Fish with many ulcers indicating an highly advanced bacterial infection due to Columnaris, will show signs of lethargy, loss of appetite leading to anorexia. It is possible to bathe this fish in a recommended dose Potassium Permanganate in order to stimulate enough appetite to commence oral medication.
I recommend immediate posting in the 911 Emergency forum if at any time you suspect a disease like this is occuring to your community of fish. Immediately you have finished posting, please then use the "Report" button at the bottom of your post to alert us the moment you're done. We will do our best to guide you through what steps need to be taken. it is very important that you provide media such as non blurry pictures and a video to support your posting.