EN
The study involved crucian carp harvested in various seasons of 2000-2002 from the Szczecin Lagoon (177 individuals) and from the Leszczyńskie Lakeland (707 individuals). The fish age was determined from scales. The length growth was back-calculated with the scale radius-corrected Vovk method in which the standard length was set at 12 mm [10]. In addition, 5 mathematical growth models (Ford-Walford, von Bertalanffy, Gompertz, the second order polynomial, and modified power function) were applied. The weight growth was followed by means of the modified von Bertalanffy equation.