With wire whisk whip together equal parts bisquick and boxed pancake mix with club soda till it's the consistency of buttermilk. Moisten fish fillets in water and then coat lightly but evenly in flour. Let dry on waxed paper 5 minutes. Spear pieces one at a time with tip of sharp knife and coat in batter. Deep fry in 385°F oil, about 4 minutes each side, till crispy and browned. Do not use tongs or coating will break apart.