Aspects Regarding the Ornamental Japanese Carp Rearing into Recirculating Systems Conditions

Abstract

To test the effect of different stocking on their growth, survival rate and number of marketable ish, juveniles of koi carp (0.4 g), Cyprinus carpio vr. Koi were cultured for 30 days in 200 L aquariums with densities of 150 exemplars and 300 exemplars respectively. Experiment was conducted in a recirculating system equipped with independent units for mechanical and biological iltration. At the end of the experiment, the data were processed in order to develop a model of growth and determination of the appropriate equation. In terms of growth, Anova test reveals signi icant differences among the four experimental groups regarding individual inal weight, which is determined by the variability of the populations tested intragroup variability as evidenced by the coef icient of variation (>50% for all experimental variants) and the distributions of individual body weight evidenced by the chart type "box and whiskers" which can be seen a large number of extreme values. Technological ef iciency did not follow a pattern directly correlated with stocking density, so the differences are practical dictated by the heterogeneity of the population, which has resulted in signi icant differences in size between individuals and the manifestation of the phenomenon of cannibalism. More researches are still needed to further optimize stocking density of Japanese Ornamental Carp in recirculating system.