Culture-Based Characterization of Bacteria Associated with Fish Pond Wastewater Undergoing Treatment Using Plants

Abstract

Fish pond wastewater management is one of the problems having the greatest impact on the environment. This untreated fish pond waste water contains organic materials, pathogenic microorganisms, nutrients and toxic compounds, which when discharged into the environment and it runs off into the water bodies in excess could cause algal bloom (eutrophication) of the receiving waters. Port Harcourt is a riverine area, many of the fish farmers discharge their wastewater direct into the water bodies or into drainages that flows into the water bodies and this act is harmful to humans and the environment as a whole. The determination of the microbiological and physicochemical characteristics and remediation of fish wastewater using Eichhornia crassipes and Pistia stratiotes were investigated. The physicochemical and microbiological parameters of fish pond wastewater were monitored at intervals from 1-70days. Fish wastewater samples were collected from twelve fish ponds (6 plastic tanks and 6 concrete tanks) using standard procedures.  Identification of bacteria was carried out using colonial morphological and biochemical characteristics of the isolates. A total of 194 bacterial isolates belonging to eleven genera were identified from the twelve fish ponds with 6 concrete tanks having  total heterotrophic bacteria, coliform counts, Salmonella Shigella counts, feacal coliform count, Vibro count,  and Pseudomonad count that ranged from 4.78 ± 0.5×104 to 5.74 ± 0.39×105, 4.06 ± 0.06 ×104, to 5.8 ± 0.43 ×105, 4.3 ± 0.24×104 to 4.99 ±0.42 ×104, 4.18 ± 0.39 ×104 to 5.08 ± 0.43 ×105 , 4.08±0.35 x 105 to 5.24±0.46 x 105 and 4.1 ± 0.3× 104 to 5.15 ± 0.44 ×104 cfu/ml, respectively and 6 plastic tanks having  total heterotrophic bacteria, coliform counts, Salmonella Shigella counts, feacal coliform count, Vibro count,  and pseudomonad count that ranged from 4.55 ± 0.46×104 to 5.74 ± 0.4×105, 4.43 ± 0.23 ×104, to 5.78 ± 0.36 ×105, 4.00 ± 0.5×104 to 5.00 ±0.47 ×105, 4.18 ± 0.39 ×104 to 5.17 ± 0.45 ×105 , 3.78±0.35x103 to 5.24 ± 0.46x105 and 3.81 ± 0.26× 103 to 5.15 ± 0.44 ×105 cfu/ml, respectively. The bacteria isolates were Staphylococcus, Micrococcus, Bacillus, Enterococcus, Proteus, Pseudomonas, E. coli, Salmonella, Klebsiella, Vibrio and Shigella sp. The presence of these organisms is an indication of lack of qualitative pond management which could become harmful to both fishes andhumans in the food web systems. Therefore, there is the need to protect our water sources for aquaculture purposes and sustainable development through the detection of aquatic infectious substances and possible control of these microbes.