At what temperature do goldfish slow down the metabolism?

[7Enigma]

Rapid acclimation is what causes the most stress (ie the sudden change when you dump a fish from a bag into a tank). The slower the acclimation the better, so its better for a small bowl to undergo a day/night change than dumping a new fish into a tank with different temps, but its degrees of stress we are trying to avoid.

Heat exchange from a liquid in our cases is mostly caused by evaporation. The conversion of liquid water into water vapor is extremely energy requiring and this causes the body of water to lose a lot of heat (energy). The radiant energy lost is pretty insignificant in most cases, EXCEPT where there is a large surface are to volume ratio as occurs in the small bowls/pots/etc. In this situation you will still lose the majority of your heat through evaporation, but will also lose significantly more through direct contact with the surroundings.

[hc8719]

just a reminder, even if its 65 degree outside, the water may very well only be 50 degrees (given its size)

i dont know if its so much that goldfish hibernate, i believe they will swim around, and eat if theres food. however they cant digest food in water below 50 degrees