When you have sick fish you need help fast. It's best if you get help from fish keepers and especially, formally-educated scientists or doctors in the field of fish medicine. This is a website dedicated to helping you find it. Here are some resources.

Koi health and medicine information

Help with the koi by symptom

Help with a fish or Koi problem using a twenty step diagnostic process. Very thorough.

Learning about fish medicines.

Subscribing to a list about Koi Health and Medicines

KoiBeginner.com - Video Tutorials