ABSTRACT
In the past fish farms were run on a five- to six-year rotation, which made the cost of production extremely high. Three-year rotation is useful in those cases where, due to climatic and other conditions, two-year rotation is not economical. Fish larger than two-year carp are readily marketable. Compared to two-year rotation, three-year rotation has certain advantages and disadvantages. The advantages of three-year rotation are that in the third year of life carp yield a greater growth rate, become larger and more tasty, and only half the quantity of stock material (yearlings) is required. The three-year rotation scheme can be implemented in a complete carp farm with a three-year rotation plan and in a partial carp farm with a two-year rotation scheme. The organization of a full-system fish farm with a three-year rotation differs from that of a fish farm with a two-year rotation by a larger number of individual categories of fish and a different percentage ratio of ponds.
