Fish enter a period of dormancy in the wintertime, rather than hibernating entirely. This is a time where their metabolisms slow down significantly, and the fishes' level of activity drops as well. This prevents the fish from expending more calories than it can afford to lose before food is readily accessible again. Fish instinctually know that cold weather is approaching when food stores become less easily accessible. To simulate this, begin feeding your fish more infrequently once temperatures drop below 70 degrees. You can stop feeding your fish entirely once it drops below 50 degrees.
Fish need fat stores in order to survive this period of dormancy. Some fish are less likely to thrive in these cold temperatures, like baby or juvenile fish or those used to warmer temperatures.
