I lost a KOI a few days ago, and I'm trueing to understand what caused it, learn a lesson and treat other fish. Sorry for the long post. I'm very upset about my stupidity and helplessness with my beloved pets.
My pond is about 1000gl with waterfall and biofilter, 40W UV. I had 8 Koi for about seven years. I bought them about 8," and they are now about 25".
A week ago, I noticed spots on some that looked like a parasite. In the photos, you may see reddish spots with the black area. Also, see strange round openings in the body. The KOI seemed active, eating well. Nothing abnormal. Water temperatures in lower 60th. I checked water chemistry, and it seemed OK. It is clear. Exchanged water two weeks ago.
Two days ago, I met the guy who worked in the fish store and asked him to stop by. He handed me a bottle of Cupramine by Seachem with about 100ml left. (Bottle says 250ml treats 1312 gallons). Suggested to feed the fish by hand and while it is close - squirt the chemical on the area. 1,5 hours later, I came back to the pond and froze in horror. Half of my pond had foam on the surface. Water is not moving in the filter. Inside the filter, I found one KOI (not the one I treated) dead, blocking the filter. Other KOI went to the bottom, motionless. Koi hid their head under the rock. They were Breathing normally. I started immediately pumping water out and exchanging it with tap water. I use a pond vacuum to suck all the foam from the surface and filter. I called the guy back. He had no explanation. He called Seachem technical support, and they had no answer about what caused it. His theory is that it was a freak coincidence. One fish went to the filter over flap, got stuck, and foaming was slime off the dead KOI. He suggested adding pond salt to the water. I'm paralyzed with fear to do anything else. Two days later, Koi are back to normal. They are active, eating well. The signs of the illness are there, and I want to take my time to treat it. Maybe monitor and see if this will heal on its own.
I welcome any ideas, suggestions on this issue.
My pond is about 1000gl with waterfall and biofilter, 40W UV. I had 8 Koi for about seven years. I bought them about 8," and they are now about 25".
A week ago, I noticed spots on some that looked like a parasite. In the photos, you may see reddish spots with the black area. Also, see strange round openings in the body. The KOI seemed active, eating well. Nothing abnormal. Water temperatures in lower 60th. I checked water chemistry, and it seemed OK. It is clear. Exchanged water two weeks ago.
Two days ago, I met the guy who worked in the fish store and asked him to stop by. He handed me a bottle of Cupramine by Seachem with about 100ml left. (Bottle says 250ml treats 1312 gallons). Suggested to feed the fish by hand and while it is close - squirt the chemical on the area. 1,5 hours later, I came back to the pond and froze in horror. Half of my pond had foam on the surface. Water is not moving in the filter. Inside the filter, I found one KOI (not the one I treated) dead, blocking the filter. Other KOI went to the bottom, motionless. Koi hid their head under the rock. They were Breathing normally. I started immediately pumping water out and exchanging it with tap water. I use a pond vacuum to suck all the foam from the surface and filter. I called the guy back. He had no explanation. He called Seachem technical support, and they had no answer about what caused it. His theory is that it was a freak coincidence. One fish went to the filter over flap, got stuck, and foaming was slime off the dead KOI. He suggested adding pond salt to the water. I'm paralyzed with fear to do anything else. Two days later, Koi are back to normal. They are active, eating well. The signs of the illness are there, and I want to take my time to treat it. Maybe monitor and see if this will heal on its own.
I welcome any ideas, suggestions on this issue.
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