Wash the fish, dab dry and cut into large pieces. Sprinkle with lemon juice. Clean and wash the peppers and cut them into fine strips. Drain pineapple on a sieve, catching the juice.
Cut the pineapple into pieces. Beat the egg white a little bit. Season fish with salt and pepper. Turn fish first in starch, then in egg white. Heat oil in a pot to 175 °C. Fry the fish for 6 minutes in portions and keep warm.
Heat 2 tablespoons of oil in a frying pan. Sauté the peppers for 2 minutes. Add pineapple. Add sweet and sour sauce and pineapple juice. Season to taste with salt, soy sauce and sambal oelek. Wash the chives and cut into small rolls.
Arrange fish and sauce on plates. Sprinkle with chives. Serve with rice.