Koi-lo wrote:
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Fungus? How is the water QUALITY in your pond? Healthy fish in good
water shouldn't be getting funguses or suffer bacterial infections.

Hmmm, water quality has been testing just fine. I haven't checked it
lately. I've been told that water temperature swings are stressful on
the fish and I assumed that was the issue. The fish only got sick when
the temperature swings up or down. When it's 20 degrees F for a week
and then 70's the following week the fish see a pretty wide temp swing.

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Float them in a plastic bag for awhile. That's a large difference. How
about a difference in PH between the tank and the pond?


I haven't checked the PH. What would be significant?