Bad bacteria or something

Outside temperatures are in the -17 to -25 degrees and the water inside is staying around 55 degrees. Life in the winter pool is still going on but without two of the koi.



I’m conjecturing that two of the koi developed some type of internal parasite. The showa was pulled out of the winter pool about a week ago because he was swimming oddly and at one point swam full speed into the wall. He was looking mostly dead for days and I expected every morning to find a dead koi. On Wednesday night, our 24″ asagi, Tarzan began doing the side stroke. It’s unfortunate that we had to leave early Thursday morning for a trip. All we could do was to put him in a quarantine tank, put some medicine in the pool and the quarantine tanks, and then cross our fingers. We returned Saturday morning to both side strokers very dead. So maybe it was swim bladder disease or maybe it was something else. We’re quite sorry to lose these two koi. Crossing my fingers that I won’t be losing any more koi to illness this winter.

The sidestrokers: