Assessment of an artificial free-flow wetland system with water hyacinth (Eichhornia crassipes) for treating fish farming effluents¤/Evaluación de un humedal artificial con Jacinto de agua (Eichhornia crassipes) para el tratamiento de efluentes piscícolas/Avaliação de uma zona húmida artificial com Jacinto de água (Eichhornia crassipes) no tratamento de efluentes piscícolas

Fish farming effluents are mainly composed of organic matter and are considered a source of environmental pollution. This study aims to evaluate the efficiency of an artificial free-flow wetland system using water hyacinth to treat fish farming effluents under various hydraulic loadings. Effluents generated from fingerling ponds of Oreochromis sp. and Piaractus brachypomus were passed through a constructed wetland system to measure ... , ... , ... , total phosphorus (TP), and Biochemical Oxygen Demand (BOD^sub 5^) removal efficiency. The hydraulic retention time was measured for six months in five assessment phases under real production conditions by using five hydraulic loadings. The hydraulic retention time of the constructed wetland system was 1.6 days, and its removal efficiency rates were: 67.9% for ... , 32.1% for BOD^sub 5^, 27.1% for ... , 23.0% for TP, and 16.7% for ... . Removal rate was positively correlated with the loading rate of total inorganic nitrogen during the five phases of this study. (ProQuest: ... denotes formulae/symbols omitted.)