Maintain a frying temperature of 375?F. If the oil is too hot, the coating will burn from the direct heat of the oil before the food cooks.
Preheating the oil to a temperature 15?F higher than its optimal deep-frying temperature allows the oil to be at its ideal temperature when cold catfish is added.
Do not add salt to catfish before deep-frying as it draws moisture to the food's surface, which will splatter when the catfish is added to the hot oil. Salt also lowers the smoke point.