Phu quoc fish sauce waters around The island are rich in seaweed and plankton which provide food for the anchovy population. However, it only since the late 1950s that the product has been recognized outside of its home island, reaching its zenith of popularity between 1965 and 1975. With increasing government subsidies of many industries in the period from 1975 to 1985, the local fish sauce craft lost market share to larger competitors, but in recent years, the popularity of the authentic Phu Quoc product has been rebounding. In 2012, Phu Quoc fish sauce was granted a European Union Protected Designation of Origin (PDO)
Fish sauce considered high-grade, and 40N is optimal. "Nước chấm" is a Vietnamese prepared fish-based condiment (also referred to as a "sauce") that is savory, lightly sweet and salty tasting, and can be sour and spicy if lime and chili peppers are added. The main components are fish sauce, water, and sugar. "Nước mắm" is made much like fish sauce, except that it is not fermented as long, and the fish is kept along with its liquid extract, not just the extract. "Mắm" can be used as a base condiment in dipping sauces with additional ingredients or used in soups or stir-fries.