Influence of stock density in productive performance of freshwater angelfish (Pterophyllum scalare)

Abstract

The present study aimed to evaluate the effects of three different stocking densities (0.33; 0.67 and 1.00 fish L^-1) on freshwater angelfish productive performance reared in aquarium. Fish were fed with commercial diets during 35 days in two daily meals. The experimental design was entirely randomized and for each density, four replicates were used. Physical and chemical water parameters: temperature, oxygen dissolved concentration and total ammonia concentration and growth performance parameters: weight gain, feed conversion, specific growth rate, final standard length, conduction factor and length uniformity were evaluated. Results were submitted to variance analysis and means were compared by Tukey’s test (α = 0.05) using the statistic program ESTAT 2.0. Mortality was not observed in any tested density. Respect to physical and chemical water parameters, total ammonia level increased significantly with stock density increasing, but they did not showed clinical signs of ammonia toxicity. As there were no significant differences between treatments, stocking density 1.00 fish L^-1 is the most indicated because it allows higher production.