I’ve got an 8,000 g pond that’s been up for a few years. A few weeks ago I noticed one fish isolating and typically head up and tail down in the corner of the pond. I assumed swim bladder issue and decided to treat with salt to 0.6 and OA. The fish went back into the big pond several days later and I thought a miracle had occurred. The fish was totally normally acting and eating and swimming normally with the others. It had previously stayed alone and swam vertically along the walls. I did scrape and scope- but found nothing.
Last Wednesday night the fish appeared normal and had been doing well- I thought. On Thursday morning the fish was floating upside down in the pond completely weak- unable to turn upright or swim from the skimmer. No sign of any trauma and no redness. I was totally stumped.
I decided to put back in a QT tank and it was able to stay upright in the QT. I decided to try OA and salt again- 3 days later and the fish had a crazy red tail fin and really red scales along the tail tube. I had been using Safe in the water those 3 days. I sedated and treated the tail with Tricide- the tail now seems to be improving and is much less red- it’s been 3 days since treatment with Tricide.
However, the fish is clearly losing weight, is weak and stays at the surface sucking water now. It still has buoyancy issues. I tried to put back into the big pond but it swims frantically as though it’s got a spine or back issue and will run into the walls. It’s a crazy situation and it’s the only fish that’s been impacted.
I don’t know if it had a bacterial infection that was partially treated originally and came back, I don’t know why the tail and tail suddenly fin went septic days later, and why this fish now stays gulping water at the surface, and if forced to swim, looks like it has a broken back. I have changed the QT water out daily with
Pond water, used safe and kept extra air for the fish, but it’s puzzling.
I know this is the nature of koi sometimes, but was just curious if someone with more experience seems something I don’t..![]()