1) I'm far from an expert, but it sounds most like a parasite or fungal type problem to me (I know that's not really nailing it down, Sunil).

2) Some diseases cross species lines, but many are family or even species specific. If I were you I wouldn't panic as long as the trout remain healthy. If they are eating well and active, they are probably not stressed - stressed fish get sick much easier than healthy fish.

3) Does their condition seem good? If they have plenty of natural food, limited interest in pellets is understandable and not, I believe, a cause for concern.

4) IIRC Bill Cody recommends a salt water dip for fish being introduced into a pond from the wild; I don't know if slightly brackish water would be useful for the problem the shiners have.

Hey Bill Cody, you out there?


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