This is my only Butterfly Koi, which I've had since 2004, and which, until today, I thought had perished in some mysterious manner over the past few days. When I checked on the pond on Friday, this Koi appeared to be fine, swimming and looking for food.
I didn't really see it during the weekend and when I was working on the pond yesterday for an hour or two, the fish was nowhere to be seen. So I began to suspect the worst and that something had happened to this koi.
Today when I went out to feed the fish, miraculously the Butterfly Koi "appeared to be fine" and was swimming a long side the other fish.
However I did notice some white discoloration on this koi's body that wasn't present previously and I cannot explain how it occurred.
Now I have no clue how this came to be. I would first suspect my waterfall pump but that seems unlikely since the flow was so weak. However the marks could be the consequence of the Koi being sucked against the intake.
Secondly, I thought perhaps one of the stones had been dislodged and had landed and pinned the Koi. This seems unlikely. Thirdly, I did notice that some of the styrofoam that I used to insulate the pond had cracked and had ended up on the top of the water's surface so I thought perhaps this was a result of ingesting the foam, but if so, why didn't the rest of the fish suffer a similar fate?
Fourthly it could have been an animal attack but again I don't suspect this is the case. The fish didn't appear to be skittish and the white color doesn't appear to be something that an animal might do.
Anyways, I will keep an eye on him and hope that he (or she) recovers from these injuries. Any input as to what you guess might have caused this is appreciated!! My guess remains the waterfall pump being the culprit but I welcome any thoughts/ideas other forum members might have.