Thread: Koi not eating, lethargic and dying

I bought 6 new koi about 3 inches long at the start of April to join my other 12 year old koi (6), carp and goldfish. After about 2 weeks my original koi stopped feeding and became lethargic and shy and have been like that ever since. The new koi, carp and goldfish are fine and feeding and growing. It's just my original koi that have stopped feeding etc.
About 2 weeks ago one of them started turning on its side and died this week.
It may be a coincidence that it started when I got the new koi but I'm not sure.
The water quality is good (nh3 0.02mgl, NO2 0.04mgl, NO3 16mgl) and I have had no problems with the koi health before this.
They look OK but are not feeding etc. I cannot see any obvious parasites or anything like that.
Does anyone have any advice please as I'm not sure what to do and want them to get better.

If you put your location somebody local may help

OK, thanks, I'm in Norfolk

If you don’t own a microscope find somebody who does you need a scrape asap to find out what’s going on

OK will try that thank you

If you were close by i would help bud.If you put your exact location chances are there will be a forum member close by

OK, thank you all. I will try speaking to one of them.