Use a brine to help the fish fillets absorb water and salt before smoking them. Fill two casserole dishes half full with room temperature water. Put 1/2 a cup of salt in each casserole dish and then lay the catfish fillets inside the salty water mixture. Set the dishes in the refrigerator for 4 hours to let them brine.
Fire up your smoker to 200 degrees. Typical smoking is done between 220-250, but a little lower temperature for these catfish is nice to have to prevent them from cooking too quickly without absorbing the smoke flavor.
Take your catfish out of the refrigerator and out of the brine mixture. Pat the fish dry with a paper towel.
Sprinkle seasoning, salt and pepper all along the top of the fillets and then drizzle hot sauce on top.
Once your smoker is up to temperature, add cherry or apple wood. Then put your catfish on the smoker grate and close the lid. Position the vents 1/2 to 3/4 open. You can adjust the vents more closed to lower the temperature or open them to increase it while you are smoking. Make sure you maintain the same temperature the entire time you are cooking.
Your catfish fillets should take about 2 to 2 1/2 hours to smoke, depending on the temperature of your smoker and their distance away from the source of the heat. Once the fish has turned flaky white with a warm center, you can take it off the smoker and let it sit for 15 minutes before serving. Letting the fish sit with foil over the top on your counter will allow the juices to redistribute throughout the fillets before serving