A friend of mine called me over this past weekend to take a look at his pond when one of his koi was found dead in the morning when he went out to feed them. He has a smaller pond with 5 - 7 comet goldfish and 3 ( now 2) foot long koi. Initial attempts with koi were a disaster as he did not do proper maintenance and had sky high nitrite and ammonia levels in the pond. He lost two batches of Koi that way and that was when he called me over the first time. His fish exhibited the classical signs of poisoning so I provided him with a regimen for maintenance which brought nitrite and ammonia levels to 0 and nitrate levels very very low. He then added the three new koi (despite my cautioning him not to do so until the pond had been expanded).
Everything went well for about a month and a half until this weekend. I came by, and tested the water first thing. All the indicators were fine so I went to look at the dead fish. The first thing I noticed (besides the foul smell) was a proliferation of whitish brown mucuos around the gills. The fish had been stored in a plastic bag for a day or so and thus I couldn't get the best look at what had gone on.
I was back at the pond today and decided to pull out some of the fish to take a closer look and see if there was something to worry about. I found that most of the goldfish had reddish lesions on their bodies and although I wasn't 100% sure it looked as though there was mucuos around their gills. The two remaining Koi thrashed around a lot so a good look wasn't possible, but they did appear to have the mucuos on their gills as well. One of them seemed to have a clearish mucuos covering a gill plate. Because of their size, colour and thrashing I wasn't able to see for sure if there were also lesions on the koi.
I've done a bit of poking around and a few things seemed to make sense, I was wondering if anyone could help me narrow it down and suggest possible treatments. The first disease that seemed to match was koi herpes virus because the fish seem alright, swimming around normally and eating and the one death was sudden and around the time of rapid and frequent temperature changes, however I did not observe the gill necrosis normally associated with the disease on the dead fish.
Another disease that seems to be a possibility is trichodina but I am not sure how to figure it out for sure without a lab at my disposal.
I saw a few other possibilities but those two seemed closest, however, I could be wrong.
If anyone knows anything on the subject; diagnosis or treatment, their help would be greatly appreciated.
Everything went well for about a month and a half until this weekend. I came by, and tested the water first thing. All the indicators were fine so I went to look at the dead fish. The first thing I noticed (besides the foul smell) was a proliferation of whitish brown mucuos around the gills. The fish had been stored in a plastic bag for a day or so and thus I couldn't get the best look at what had gone on.
I was back at the pond today and decided to pull out some of the fish to take a closer look and see if there was something to worry about. I found that most of the goldfish had reddish lesions on their bodies and although I wasn't 100% sure it looked as though there was mucuos around their gills. The two remaining Koi thrashed around a lot so a good look wasn't possible, but they did appear to have the mucuos on their gills as well. One of them seemed to have a clearish mucuos covering a gill plate. Because of their size, colour and thrashing I wasn't able to see for sure if there were also lesions on the koi.
I've done a bit of poking around and a few things seemed to make sense, I was wondering if anyone could help me narrow it down and suggest possible treatments. The first disease that seemed to match was koi herpes virus because the fish seem alright, swimming around normally and eating and the one death was sudden and around the time of rapid and frequent temperature changes, however I did not observe the gill necrosis normally associated with the disease on the dead fish.
Another disease that seems to be a possibility is trichodina but I am not sure how to figure it out for sure without a lab at my disposal.
I saw a few other possibilities but those two seemed closest, however, I could be wrong.
If anyone knows anything on the subject; diagnosis or treatment, their help would be greatly appreciated.
