In order to investigate the influence of intraspecific hybridization on the growth rate of fish, the aquarium fish Trichogaster trichopterus (Pallas, 1770), namely the Blue and Gold variations, were chosen as the object of study. The research aimed to elucidate the differences regarding the growth rate between the individuals obtained as a result of intraspecific hybridization and the non-hybridized parental forms. In the descendants obtained by hybridization, a significant variation of the parameters can be seen, compared to the non-hybridized specimens. Starting from the very first days, a significant increase in weight is observed in the hybrid fish. Already from the
initial stage, the hybrid offspring exceed the length of the non-hybrid offspring by about 40 %. Intraspecific hybridization can be successfully used as a method to enhance the growth rate of the ornamental fish Trichogaster trichopterus.
