1. Quarter tomatoes; slice ginger; peel, core and slice pineapple; cut scallion, Chinese celery and culantro in sections; slice chilli pepper, set aside.
2. Rinse red sea bream, make sure all the blood and slime inside is thoroughly cleaned, then cut two to three slits on both sides of the fish, cook in boiling water for five minutes.
3. Add tomato and pineapple, cover lid and cook three minutes.
4. When the fish is cooked, add chilli pepper, season with chicken powder, salt, sugar and fish sauce.
5. When the soup boils, add Chinese celery, scallion and culantro, bring to a boil. Turn off heat, add lime juice and serve.