Qualidade da água do cultivo de tilápias (Oreochromis niloticus) em um sistema de recirculação de água (SRA)

Abstract

Aquaculture has been gaining more and more space in Brazil and in the world, due to the expansion of aquaculture activities, issues related to the environmental sustainability of production systems arise through the direct use of water resources, which can affect the quality and quantity of water available in these aquacultures. . Given this, it is necessary to search for viable and low-cost mechanisms that make it possible to minimize such impacts using the available natural resources in a sustainable way. The objective of the present work is to make a water quality diagnosis of a water quality kit, which are available and access recirculation system with brita and expanded clay filters using the ible to any producer. A water recirculation system containing a box with a capacity of 250 L was used where the juveniles of Oreochromis niloticus that produced the effluent were allocated, and 9 boxes with 50 L capacity where the filters were placed totally randomly. Three different types of filter (Brita stone filter, expanded clay filter and mixed clay and stone filter) were used with three replicates each. The variables (water temperature, dissolved oxygen, pH, conductivity, ammonia, nitrite, alkalinity and hardness), water in the culture tank and the boxes containing the filters were measured. Regarding the filters, the one that did not obtain greater result in the withdrawal of the nitrogen compounds was the one of expanded clay when compared to the other filters. It can then be considered that the kit of water quality Alfa Kit, brings us some gaps in relation to its analyzes having long intervals from one color to another to be analyzed. With this, without giving us an accurate result of the analysis. But, on the other hand, it is an alternative for the producer in knowing what situation his water is found to be a viable option in financial question. When comparing the data with CONAMA Resolution 357/05, the work shows that the averages obtained throughout the analysis process came within the established standard, being able to be released into the receiving bodies.