|
warming up quickly ( 5 degrees an hour) is not unreasonable. We used to go by 2-3 degrees an hour in this hobby. But that is from the tropical fish hobby and does not apply to koi, as it turns out.
Many hobbyists have observed one common thing- koi experience no ill effect of even as much as a 10 degree transfer UPWARD- meaning from cooler to warmer water. But they do tend to react badly to moves down in temperature of ten degrees or more.
But all this has to be taken against the backdrop of what condition the fish are in. If they are weak and showing signs of equlibrium loss and red skin, I would not test/challenge their metabolisms by transfer to any extreme, up or down- temperature, pH or even hardness. Slow and steady is much better for weak koi.
The very best way to do this is to get a little giant and run some pondwater inside to the QT tank ( 1000 plus gallons). Then transfer the fish to that 'known' water. You then can allow the water to climb in temperature. A large body of water will take hours to rise to ambient levels indoors. JR
|