It sounds like something is way off base and any resident pathogoens are taking advantage of weakened Koi.
First, what are your water parameters? PH, KH, Ammonia, Nitrite, Nitrate etc and what is your normal maintenance regime? Has there been any recent changes or additions to the pond that may have upset the natural balance of the pond eco system? Have you introduced new fish from one or more sources?
Try and provide as much information as you can and I will take it from there.
Alan.
Posted on Aug 15, 2005, 6:47 PM from IP address 213.120.101.21