| Marco: I've been thinking about what I posted and the pics you posted. Several years ago I acquired a small Showa that had been shipped from Japan to a dealer in the U.S., who immediately took it on a 14 hour road trip to a show, where I bought it. That poor fish had been bounced around in Japan, put through all the rough handling of air cargo, bounced along the highways and put in a sales vat. Along the way, it had multiple potassium permanganate dosings to rid it of parasites. Within 2 weeks of arriving at my house, it had fin rot much like your pics show. But, the fish had a healthy appetite and no symptoms of parasites. The idea of injecting antibiotics was not anything I was prepared for, and the fish had not cost as much as the antibiotics would have cost. I isolated the koi in a hospital tank with a dose of 400mg erythromycin per 10 gallons (U.S.) of water dissolved in the water, with a dose of 200mg per 10 gals. being repeated every 24 hours for 5 days. No food during that time. A 50% water change was performed daily using water stored overnight with the identical temperature. After the 5 days, the koi went into a small, shallow pond which had temperatures ranging in the mid-70sF. At that point the bloody streaks in the fins had improved quite a bit, but were not gone. I fed it medicated food only. It had a couple of goldfish as company, and the pond was shaded from direct sun all but a few hours of the day, with shady cover. After another 7-10 days, the fins were clear. After another month, the fins had re-grown. There were no lasting visible defects.
The point of the story is that I jumped to an assumption that you likely had parasites. Maybe not. Stress from environmental factors may have weakened the fish so they became susceptible to an infection. Search for the possible causes of stress to your fish. I suspect flukes are there, but maybe it is something else that triggered the infection.
Second, I wanted you to know that it really is possible to save them without injecting antibiotics. Often koikeepers quickly go for injections, forgetting that not everyone has access to the antibiotics, nor the money for it, nor the knowledge of what to do. So, do your best for the koi. We are still wishing you luck. |