Preheat the oil in the fryer to 350°F (180°C). Place a wire rack on a baking sheet or line it with paper towel. Preheat the oven to 200°F (100°C), to keep the shrimp warm as you cook them.
In a bowl, combine 1 cup (120 g) of the flour with the salt and baking soda. Gradually whisk in the water and vinegar, whisking just until the batter is smooth.
In a large shallow bowl, place the remaining 1/2 cup (60 g) of flour. In another shallow bowl, place the rice cereal.
Dredge the shrimp in the flour, shaking off any excess. Dip the shrimps in the batter, one at a time, holding them by the tail. Immediately dredge them in the rice cereal. Place them in the fryer, shaking the basket lightly so they do not stick. Fry 5 shrimp at a time for 2 to 3 minutes, until golden brown. Drain on the baking sheet.
Sprinkle the shrimp with paprika and salt. Serve with sweet and sour pepper sauce.
Pastry flour contains less gluten and results in a crispier tempura batter.