In a medium pot, bring water to a boil. Once the water starts boiling, add labanos, tomatoes, onions and kamias. Simmer over low heat for about 10-15 minutes.
Do a taste test, and check the sourness of the soup. Once the soup is sour enough, add the slices of bangus and let it cook for a few minutes.
Add the other vegetables, like sitaw, talong, tanglad and siling haba. Let it cook for 2-3 minutes.