African catfish performs optimally in temperature above 25 degree Celsius. This does not mean temperature below 25 degree Celsius will kill your fish. It will only reduce the growth potential of your stock.
Catfish cultured in a deep earthen pond of depth between 3 to 6 feet can easily adjust to temperature by swimming to the warmer or cooler depth. However, studies have shown that shallow ponds are more affected by change in temperature (cold or hot temperature). Whether in earthen ponds or other types of ponds, cold weather affects the performance of African catfish and its environment in different ways as explained in this article.