Análise do sistema de bioflocos para o tratamento da água na piscicultura no Alto Sertão Paraibano.

Abstract

The objective of this study was to evaluate the production of Nile tilapia (Oreochromis niloticus), cultivated in a biofloc system, with emphasis on the effect of production on water quality, as well as its zootechnical performance. This work was developed at JWN Farm, located in the city of Coremas - PB, Brazil, for 77 days. The fish were transferred from earth tanks with average weight of 200g, to four circular tanks with 200 m³ of total capacity. Among the chemical physical parameters under study alkalinity was modified during the course of the crop, requiring adequate management for its control. Another parameter modified was the pH, due to the alterations resulting from the alkalinity concentration. In relation to nitrogen compounds, ammonia increased during the course of cultivation, but in this case there is a direct relationship with the growth and quantity of fish cultivated, as well as the reduction of the amount of bioflocos present in the culture water. In relation to the zootechnical performance, the survival remained close to 100 ℅, while the feed conversion was presented in the range of 1.12 in the crop, being thus satisfactory. Regarding the effluents produced by the crop, the levels analyzed were within the range allowed for its launch. Therefore, it was concluded that the biofloc system, when properly managed, can become a solution for regions with low water availability.