| Question | Answer | Article | |
| What is the cause of these lesions, which resemble molten candlewax, on the dorsal fin of this koi? | Carp pox, caused by infection with Herpesvirus cyprini, also called cyprinid herpesvirus 1 (CHV1). These lesions are often classified as neoplasia but are basically an epidermal hyperplasia. |
Link to Article | |
| How can this disease be controlled? | The disease is often seasonal and usually affects only a few fish in the pond. Lesions develop in low water temperatures (winter/spring) and regress when water temperatures increase. Treatment is seldom required because the disease is rarely fatal and is usually self-limiting. Lesions may recur the following year. |
Link to Article | |
