When is it too late in the season to add new fish?

[Meyer Jordan]

"It is the process of preparing them to fast for a prolonged period."--rodsboys

Are we talking about feeding?
Somewhere in ancient history, someone arrived at the conclusion that fish stopped eating when the water temperature fell below a arbitrary figure. Today that figure is usually 50F, although I have seen 55F mentioned.
Fish, in fact, will continue to eat, if able, as long as their metabolism is functioning. Conversely they will burn no more energy than is needed based on this metabolic rate. As long as there is level of nutrients available to match this metabolic demand, there is no demand on or need for stored energy (Fat).
If the fish are in a pond that is overstocked and/or has limited periphyton growth then, yes, there will be a need for stored energy. A fish cannot be 'prepared' for the low temps of Winter. This is already a naturally occurring process that is triggered by the falling temperatures and this force is immensely more powerful than any artificial change in diet. Nature takes care of its own...always has and always will. It is the external 'tinkering' that bypasses and/or alters these natural processes that trigger most of the issues faced concerning the health of a pond and its inhabitants.

 

[rodsboys]

Interesting. Never though of that. I assumed the mass amount of weight on my fish that seems to not be there in the spring meant that they simple lost the weight due to not taking in any food, but still burning (even at a significantly reduced rate) their energy/fat stores.
My fish are without food for 7 months.

 

[tbendl]

I think that's the "tinkering" part he was talking about.

 

[MitchM]

My thinking is that the water temperature may cause the fish to alter their own diet - higher temperatures they look for more vegetable matter, lower temperatures they look for more protein/fat.
Perhaps.
That's what I do, anyways...

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