Size range: 15-19 cm, 18-20 cm, 20-24 cm, 25-30 cm. Fish headless, without tail, fins, scales, piece/individual freeze. Moderately fatty fish contains from 1 to 4 percent of fat and is classified as the diet product. Types of Flounder: Yellowfin, Whitebelly, Bluefin, Flat-headed. Habitats: European coasts, White Sea, Sea of Okhotsk, Barents Sea, Black Sea, and Baltic Sea. Flounder is a good source of polyunsaturated fatty acids, and nutritionists recommend eating this fish twice a week. The Flounder fillet contains omega-3 and omega-6 fatty acids in the right proportions for the body, vitamins D, E and A.