Sinigang is a soup or stew, usually cook with meat or seafood by boiling it with a sour base such as Tamarind, Guava, Calamansi, Kamias, Santol or Unripe Mango. It is a common dish of the Filipino culture.
This video shows another recipe for sinigang na salmon.
Find it online: https://pilipinasrecipes.com/sinigang-na-salmon-recipe/