Carp Edema Virus Disease or Koi Sleepy Disease article.

Back in the 90s and early 2000s we used to see occasional ponds of fish that would be trying to fall asleep. Some of the fish would roll on their sides and they wouldn’t come up until you disturb them. Then they would “shake it off” and act like nothing was wrong. This practically only happened in very very cold water, and in systems that were infected with lots of ciliated, protozoan, parasites, particularly, Trichodina. I always thought it was just a fulminating stress response. You know, cold, parasites, recent transport, equals stress.
The treatment we used, which seemed to be successful. Most of the time was warming the fish into some range that allowed them to think a little. Most of the time they stopped ‘sleeping’ when they got about 55 or 60 DF. and after we cleared their parasite burden.
Looking back on it, for all I know, that was just the passage of time and not the temperature or clearing your parasites. But that’s what we did. And we didn’t have mortalities. Besides the first couple that got me the phone call anyway.
And, of course, we also don’t know that it was koi edema virus. 
What little information I have, I put over at my website

Author: admin