Evaluation of water quality parameters of an aquaponic system using red-bellied pacu (Piaractus brachypomus), strawberry (Fragaria x ananassa) and basil (Ocimum basilicum)

Abstract

The physicochemical and microbiological parameters of water were evaluated in an aquaponic system for the production of red-bellied pacu ("cachama blanca"), strawberry and basil.Water samples were analyzed at the inlets and outlets of the system and in the three seeding methods employed -Nutrient Film Technique (NFT), floating root, and gravel bed -over three months.At the end of the productive process, nitrifying bacteria normal for this type of system were found.Chitinolytic bacteria, fundamental to aquatic cultures, were also growing, with colonies being found of bacteria of the Bacillus genus that assist in improving conditions in this environment, in particular Bacillus subtilis, important in modification of the aquaculture microbiota.Similarly, the presence was identified of phosphorus solubilizing fungi, which improve nodulation, nitrogen fixation, growth and crop yield.In the physicochemical parameters, variation in the final temperature was observed in each crop and bed.In terms of pH, variations were found in the final measurements.The ammonium variable showed decreases in the average final value, while nitrites remained stable at the beginning and at the end of each measurement in both cultures and in each bed.Finally, nitrate concentrations were seen to decrease in the floating beds for both cultures, by more than 20 mg/L.