I had a 3000 gallon cement pond with 8 koi. I have had these koi since they were 3 inches long and now they are 25+ pounds. Due to the cement pond having numerous problems, I had it demolished and a new liner pond built. The new pond is 4500 gallons. The fish were removed and placed in two holding tubs for about two weeks before they were transferred to the new pond. While they were in the holding tanks, water was tested daily.
The fish were placed in the new pond one week ago. This water is also being tested on a regular basis. They are showing signs of what I believe to be stress. All 8 of them are laying on the floor of the pond and hardly move. They appear lethargic and do not show any interest in anything. We did a 20% water change yesterday and there is maybe a 5% improvement.
I do not have any experience with this kind of problem. I feel bad that now they have a much nicer environment, they are just laying on the bottom of the pond. Can someone give me any ideas on how to deal with this situation?
Thanks much...Karin