Cause of fish lose: The 2015 Grand Prize Winner!

Failure to Quarantine New Fish before you place them in your pond
The Winner for the fourth year in a row has not changed.
Failure To Quarantine New Fish still wins the #1 Prize!!

 

Wins the 2014 Grand Prize for the cause of koi sickness and death

Runner Ups
Poor water quality
Waiting too long to treat your sick fish
Using the wrong treatment, delays proper treatment

 

Wintertime Losses
Lack of Oxygen
Pond Freezing over
Buildup of toxic Ammonia
Circulating freezing cold water around your fish