This disease starts from a cut, bruise, or open wound attacked by parasites with the secondary infection being taken over by bacteria. It is caused mostly by Aeromonas and Epistylis. Usually, within a few days, the infected area becomes red and then a few scales drop off revealing the muscle. If not treated at this stage, more flesh will be eaten away and parts of the bone and internal organs will appear.

In the early stages of the disease, brushing with Mercurochrome is usually sufficient treatment. If this does not cure it, then antibiotic injections with Kanamycin or Chloromycetin can be effective. This disease occurs just as the cold season begins to warm. Since cooler temperatures seem to activate this bacterial type, an increased water temperature in the treatment tank, plus antibiotic injections have been effective. A temperature of 75 to 85 degrees F is usually sufficient.

*Information on this page is an excerpt from "KOI" by Grant Fujita, available at the AKCA online bookstore.