(Make chips: Peel potato and cut into 12 wedges. Pour 3 cups water into a medium bowl and submerge potato wedges for 15 minutes. Drain off water and replace with fresh water. Soak wedges for 15 more minutes.)

(Meanwhile, prepare fish: Mix together flour, cornstarch, salt, garlic powder, baking soda, and baking powder in a large bowl. Pour in 1/2 cup malt beer and stir to combine. If batter seems too thick, add remaining beer 1 tablespoon at a time.)

(Place cod fillets on a rimmed baking sheet lined with a drip rack. Spoon 1/2 of the batter over fillets. Place the rack in the freezer to allow batter to solidify, about 35 minutes. Flip fillets over and coat the other side with remaining batter. Return to the freezer for 35 more minutes.)

(Preheat the air fryer to 400 degrees F (200 degrees C) for 8 minutes.)

(Cook frozen fish fillets in the preheated air fryer for 15 minutes, flipping at the halfway point.)

(Meanwhile, drain off water from potato wedges and blot dry with a paper towel. Place in a medium bowl and add oil, salt, and pepper; toss until well coated.)

(Cook coated potato wedges in the preheated air fryer for 15 minutes.)