Effectiveness of Eichhornia Crassipes in the Treatment of Aquaculture Effluent From a Fish Farm in Benin City, Nigeria

Abstract

Aquaculture production has seen much increase in Nigeria in recent times due to the rise in fish farming occasioned by the availability of water and materials for setting up, the profit turn-over, increase in demand for fish, and the effort to curb the rising youth unemployment rate. However, this massive surge of interest in aquaculture and fish farming is accompanied by the challenge of pollution as the effluent from aquacultural settings gets discharged into nearby water bodies hence the need for remediation. Aquatic plants have been used to remediate polluted water bodies and possess many advantages over other methods. Therefore, this study aimed to investigate the effectiveness of Eichhornia crassipes in the clean-up of aquaculture effluent. Wastewater collected from a commercial fish pond in Benin City, Nigeria, were divided into two treatment groups. One group was diluted with an equal volume of distilled water (50%), and the other group consisted of 100% wastewater. Distilled water was used as a control (0%). The samples were treated with Eichhornia crassipes for 14 days, following which samples were collected for physicochemical analysis. The result showed that E. crassipes reduced significantly the pH from 7.44 to 5.98 and 7.28 to 6.10 in the 50% and 100% effluent samples, respectively. The removal efficiency of E. crassipes in the 100% effluent sample was 69% for phosphate, and 94% for nitrate. The study suggests that E. crassipes may be effective in improving the quality of aquaculture wastewater.