Adapted from google.com
Dip moistened fish pieces evenly but lightly in the flour. Dust off any excess flour and allow pieces to air dry on waxed paper, about 5 minutes. Whip the pancake mix with the club soda to the consistency of buttermilk− pourable, but not too thin and not too thick. Beat in the onion powder and seasoned salt. Dip floured fillets into batter and drop into 425 oil in heavy saucepan using meat thermometer. Brown about 4 minutes per side. Arrange on cookie sheet in 325 oven until all pieces have been fried.