Pond Parasites

Question
Hello Leigh-

I have just recently started a pond. I have lily and water hyacinths in there. I have a mixture between goldfish and koi. We have only had about 2 months. First we started out with the goldfish and they did good about 3 weeks later I put Koi in. One by one the Koi are dying we are down to 3 left start out with 6. I can't figure out why they are dying at first I thought maybe they were sick or something. The PH is fine from what the pond place tells us it is 7 which i guess is right on the money. When I came home from work on Friday as well as today another one was dead. I pulled the filter out and seen little teenie tiny red worms in the filter. I am not sure if this is what is killing them or even for that matter what they could be. The goldfish are doing great its just the koi's. Any help would be greatly appreciated.

Thank you
Stephanie

Answer
It was probably sick koi to begin with I am not too familiar with fish diseases. If the goldfish are happy I would let it go like that for a while before introducing any more Koi. I don't think the red worms are a factor I have had them and they don't seem to affect anything. You might look in the pond store for some kind of a fish disease chemical if your pond is not too big. If the goldfish stay OK for a month I think you can assume the Koi were sick when you got them.

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