The study compared the chemical composition of four types of two-year-old fish raised in the same conditions. They found that the moisture content varied among the fish species, with common carp having the lowest and tench the highest. Protein content was highest in silver carp, while fat content was highest in common carp. The ash content was highest in tench. The fatty acid composition differed between the fish species, with tench having the most saturated fatty acids, common carp having the most monounsaturated fatty acids, and silver carp having the most polyunsaturated fatty acids. Overall, the freshwater fish examined were found to have high nutritional value due to their favorable fatty acid composition.