Fishpond Wastewater Research Articles

Development of Ag-doped on multi-walled carbon nanotubes for the treatment of fish pond effluent

The treatment of fish pond wastewater utilizing nanocomposites by batch adsorption using purified carbon nanotubes and silver-doped carbon nanotubes (CNTs) as nano-adsorbents was explored in this study. Ultraviolet spectroscopy, X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM) were used to confirm the biosynthesized AgNPs. The metallic silver is associated with the peaks in the XRD pattern, and HRTEM studies indicated that AgNPs are between particle sizes of 11.12 and 15.39 nm. Purified carbon nanotubes (P-CNTs) and silver-doped carbon nanotubes (Ag-CNTs) were produced using a Fe–Ni/kaolin catalyst in a catalytic chemical vapour deposition process, followed by acid purification and doped with silver nanoparticles, respectively. HRTEM, HRSEM, FTIR, and BET were used to characterize the as-synthesized CNTs, P-CNTs, and Ag-CNTs. Both unpurified and purified CNTs were tube-like, extremely porous, and crystalline, with Ag-CNTs having a higher surface area (1068 m2/g) greater than P-CNTs (268.40 m2/g). The batch adsorption process was used to investigate the adsorption behaviour of P-CNTs and Ag-CNTs to remove Fe, Mn, and Zn from fish pond effluent as a function of contact time, adsorbent dosage, and temperature. The Freundlich isotherm described equilibrium sorption data better than the Langmuir isotherm, and the adsorption kinetics fit well with the pseudo-second-order model. A thermodynamic study of the adsorption process found that the change in Gibbs free energy was negative, indicating that the adsorption process was feasible and spontaneous. Consequently, it has been demonstrated that removing heavy metals from aquatic effluent using Ag-doped CNTs is effective in aquaculture.

EVALUATION OF THE POTENTIAL OF ONION PEEL COMPOSITE AS AN ADSORBENT FOR THE REMOVAL OF CATIONS IN FISH POND WASTEWATER

Toxic metals in wastewater when discharge in to the environment can accumulate in vital organs when ingested, and get concentrated through the food chain causing poisonous effects to living organisms. Alumina modified onion peel composite was used in this study as an adsorbent for the removal of lead, nickel, chromium, copper and zinc ions from Fish pond wastewater via adsorption process. Batch adsorption experiments were conducted to examine the effect of adsorbent dosage, pH, adsorbate concentration, and contact time on the adsorption of the cations. The optimum adsorbent dosage was 0.3g, pH was 2, contact time was 60 mins and initial concentration was found to be 10 mg/l. The concentration of metal ions present were analyzed using Atomic Absorption Spectrophotometer. The characterization by Fourier Transform Infrared (FTIR) showed absorbance peaks that correspond to hydroxyl, aldehyde, alkyl, amide and carboxylic acid functional groups. These functional groups helped in enhancing the adsorption of the metal ions. Scanning Electron microscope (SEM) analysis was carried out for the morphological characteristics of the adsorbent, before and after adsorption. The experimental isotherm data were analyzed using linear form of Langmuir and Freundlich isotherm models. The Langmuir isotherm provided the best fit for the sorption of Zn2+, Cu2+, Cr3+ and Pb2+ ions with the correlation coefficient (R2) as 0.981, 0.994, 0.9192 and 0.9478 respectively while the Freundlich isotherm had a best fit for the sorption of Ni2+ with the correlation coefficient (R2) of 0.9574. The maximum monolayer adsorption (qm) for copper was found to be the highest

Intensified biogas upgrading via various wastewater using microchannel

In this article, several ideas have been proposed for CO2 separation and biogas upgrading using industrial wastewater. Synthetic gas (60% CH4, 40% CO2) has been upgrading in atmospheric pressure in a T-shaped microchannel using municipal, meat processing, water distillation, dairy, caustic, and fish pond wastewater. The municipal, fish pond, and meat processing wastewater contain ammonia, while dairy, and water distillation wastewater contains Ca2+, and Mg2+. Also, the caustic refinery wastewater contains NaOH, with higher alkalinity for CO2 separation. The effect of temperature, gas, and liquid flow rate were investigated. RSM analysis provided a function of three dependent variables of quadratic model for prediction of responses (CO2 removal efficiency and total mass transfer in gas phase) by each absorbent, and all models were meaningful. In addition, given that all R2 values were greater than 0.94, it was indicated that experimental values for removal of CO2 and mass transfer coefficient are favorably consistent with the values of the model. Maximum CO2 absorption was obtained at 30°C, liquid flow rate of 150 mL/hr, and biogas flow rate of 50 mL/min. According to the results obtained for mass transfer coefficient, these coefficients are at least 5 to 22 times greater than mass transfer coefficient in chemical absorption in normal absorption towers, such as packed towers.

The effect of irrigation with fish pond waste water on the quality and yield of tomato under green houses

This study was carried out during the seasons of 2008_2009 to study effect of irrigation with fish culture effluent on quality and Lycopersicum esculentum (under green house) yield of tomato. The experiment consisted of four treatments: Irrigation with freshwater. (control), irrigation with fish culture effluent, irrigation alternately with fish culture effluent twice and freshwater once, irrigation alternately with fish culture effluent once and freshwater once. The experiment was done according to the completely randomized block design with four replicates. Soil and water samples were collected and analyzed. Results of the study showed: The irrigation in waste water fish ponds adds positive effect on quality and yield of Tomato under green house. This effect of water was on the irrigation with fishculture effluent increase the yield 17.82 Kg/m2 firstly followed by the treatment of irrigation alternately with fish culture effluent twice and freshwater once by yielding 15.47 Kg/m2. After that it was on irrigation alternately with fish culture effluent once and freshwater once by yielding 12.42 Kg/m2 comparing with-irrigation of freshwater. Which give lower yield 8.88 Kg/m2.

Microalgae cultivation in wastewater effluent from tilapia culture pond for enhanced bioethanol production.

The large number of wastewaters are generated because of the various production processes. Vegetable and fish processing can be considered an important industry for wastewater generation. The essential method for completing this waste is to digest the organic matter using anaerobic digestion followed by aerobic wastewater treatment processes; however, wastewater from tilapia culture pond retains considerable quantities of inorganic substances, particularly nutrients like nitrogen and phosphorus. The optimal conditions for cultivating Chlorella vulgaris from wastewater treatment effluent from tilapia culture pond were investigated in this study. The appropriate conditions were found to be 10% initial stock suspension, 20 cm depth, and 12 days of culture conditions. C. vulgaris had an optical density of 0.649, a cell density of 17.68 × 105 cells/mL, and biomass of 0.376 ± 94.21 mg/L after cultivation. Discharged wastewater from the fishpond was utilized for the improved growth of microalgae and obtained biomass was used for bioethanol production. This study verified that fishpond wastewater is the best source of nutrients for algal mass production and biofuel applications.

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

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.

Fabrication of PVA/Ag-TiO2 nanofiber mats for visible-light-active photocatalysis

Visible-light-active nanomaterials for the photodegradation of organic compound in water were fabricated using facile techniques. In this work, anatase titanium dioxide (TiO2) nanoparticles (NPs) were coupled with plasma-reduced silver (Ag) to shift its sensitivity to visible light. The NPs were subsequently immobilized in electrospun poly(vinyl alcohol) (PVA). The PVA/Ag-TiO2 nanofiber mats (NFMs) were subjected to plasma etching to partially expose the embedded NPs and improve photosensitivity. The NFM sample exposed to oxygen plasma exhibited 51% removal of methylene blue in water under visible light irradiation. Compared to the untreated NFM sample, plasma treatment resulted to a 20% increase in dye removal efficiency. In addition, total organic carbon (TOC) analysis of fishpond wastewater using the NFMs under visible-light irradiation was conducted. With the NFMs, there was a 32% decrease in TOC concentration while in the absence of the catalyst, a 142% increase was measured. The results showed the effectivity of the catalysts to counter the biochemical reactions that took place in the actual wastewater samples. Moreover, the immobilization of visible-light-active Ag-TiO2 NPs in PVA would extend its service life as well as minimize its environmental risk, making the NFMs ideal for removing organic compounds in wastewater.

Electrocoagulation-flocculation of aquaculture effluent using hybrid iron and aluminium electrodes: A comparative study

This work investigated the treatment of fish pond wastewater (FPW) using electrocoagulation – flocculation (ECF) through aluminium (Al) and iron (Fe) electro-coagulants. The feasibility of using this method has been determined in terms of turbidity (TUR), biochemical demand oxygen (BOD), chemical demand oxygen (COD), and reduction of colour (COL). The study analysed the role of pH, current dosage, electrolysis time, settling time, temperature, and concentration of NaCl on the ECF process. Also, the influence of using the hybrid of Al and Fe in different configurations (Al-Al, Fe-Fe, Fe-Al, and Al-Fe) was taken into account for the ECF process. The perikinetics kinetics of the process flocculation was studied. The coefficient of regression (R2) was used to confirm the theoretical applicability of perikinetics flocculation. The forecast of the time evolution of aggregating particles or species was included. The optimum pH was 2. Al-Al electrode had a higher TUR removal (87.87%). Fe-Fe electrodes were the best for reducing COL (73.56%). Al-Al was proven to be the best electrode configuration for BOD removal (76.90%) and COD removal (86.4 %). The ECF kinetic data partially followed Von Smoluchowski's equation for the Brownian perikinetics flocculation theory. The mechanisms that accounted for the distribution of particles were sweep flocculation and charge neutralisation. The ECF was very effective for reducing FPW pollutants.

Bacteria Screening with Sufficient Nitrate Extraction from Wastewater

Search for effective biological strain for use to remedy water pollution has been limited. This study was performed to search for effective bacteria capable of extracting nitrate from wastewater. Samples from abattoir inside (Abi) and abattoir outside (Abt), fishpond of kwalkwalawa (Fpk) and mabera fishpond (Fpm) wastewater were used. Using conventional standard plate technique as 1.96×107 cfu/ml (Abi) had highest bacteria count while 1.05×107 cfu/ml (Fpk) had minimal. The obtained pure colonies were morphologically and biochemically characterized including two Enterobacter specie, Proteus and Pseudomonas specie. The isolated organisms were used as a test organism for the removal of nitrate present in high nitrate containing medium. Prior to the extraction, the wastewater samples were physicochemically analyzed using parameters like color, odor, pH, alkalinity, hardness, temperature and nitrate. For nitrate extraction, bacteria were inoculated in a separate tubes containing nitrate broth, incubated in a rotary shaker 150rpm at 37°C for 16hrs. The supernatant from 10minutes centrifuged culture were used for nitrate removal evaluation after a series of reaction and stop using spectrophotometer at 420nm. The absorbance 0.732 proteus specie after estimation of nitrate in a medium was maximal while Enterobacter specie 0.574 was minimal. Meanwhile, two of the Enterobacter specie has similar absorbance 0.012 while Proteus and Pseudomonas species had 0.016 and 0.010 respectively in the nitrate concentration removed within the media. The nitrate present in the medium was compared with a known standard curve prepared with NaNO3 at 100-1000 ppm. The result indicated that bacteria from fish pond wastewaters had highest potential for extracting nitrate and that inherent bacteria are capable of removing pollutant nitrate and the bacteria may be able to remove nitrate efficiently if genetically engineered.

Spirogyra cultured in fishpond wastewater for biomass generation

Algae are aquatic organisms that can be found in a wide range of water bodies. Algae, a form of aquatic organism, is found in many different water types. Besides being relatively easy to maintain, algae are also numerous, making them a good choice for biomass production. The filamentous Spirogyra sp., a common green alga, tends to grow in freshwater. It is said that this macroalga has a wide variety of biotechnological applications. Research in this area highlights biomass's creation and builds on our understanding of the composition of macroalgae generated in fish farm wastewater. A study of Spirogyra in undisturbed fish farm wastewater was conducted in this study. Various algal species were evaluated for their qualities, including biomass yields and productivity, protein, fat, and carbohydrates. This investigation has confirmed that the nutrients in fish farm effluent are suitable for cultivating algal biomass. Protein, lipid, and carbohydrate levels in unaltered fish farm effluent were the highest for Spirogyra, with percentages of 19.03, 8.38, and 45.71%, respectively. Thus, it was the most suitable organism for various biomass-based applications and nutrient removal.

Effects of Biofilms on Ammonium Removal Efficiency in Fish Pond Effluents

Treatment of wastewater in fish ponds effluent is an effort to reduce the impact of pollutants contained in the wastewater so that it can be disposed into the aquatic environment safely. The purpose of this study is to understand and analyze the effect of inoculant sources on removing of total ammonium in vanamae shrimp and marguensis shrimp pond wastewater, and to pre-design the technology for treating high-salinity organic waste with biological wastewater treatment using natural microorganisms. The study was conducted using a laboratory-scale reactor. At the beginning of the study, adherent biofilm media was planted at the bottom of the sea with a depth of 1.5 m for three weeks to grow nitrifying bacteria, then applied to treat fish pond wastewater. The results showed that the efficiency of ammonium reduction with adherent media from Telukawur is 74% while adherent media from Panjang Island is 66% with declining and fluctuating trends every day. The extensive -scale application for treating wastewater from brackishwater aquaculture is designed with 4 processing units, a 15.5 m x 7.7 m x 1.5 m sedimentation basin, a 10.5 m x 3.5 m x 1.5 m anaerobic basin, a 13 m x 13 m x 1.5 m aerobic basin, and a 15.5 m x 7.7 m x 1.5 m effluent basin. It concludes that biofilm adhesion technology from Panjang Island waters and Telukawur waters can work efficiently in removing ammonium concentration.

Fish Pond Effluent Effect on Physicochemical Properties of Soils in Southern Guinea Savanna, Nigeria

This work studied the effect of fish pond wastewater, proximate and mineral analyses of the fish feeds from commercial fish ponds on receiving soils in the southern Guinea Savanna ecological zone of Minna, Nigeria. The study con-ducted during the dry seasons of the years 2015 and 2016 between January and May. Four sets of soil samples were collected at varying distances from the various fish ponds and analysed for physicochemical properties, Particle size analysis and Exchangeable Acidity. Similarly, two different sets of water samples were collected each from various farms studied and analysed for physicochemical properties such as pH, Ec (Electrical conductivity), TDS (Total dissolved solids), Alkalinity, Total Hardness, Turbidity, Temperature, DO (Dissolved Oxygen), BOD (Biological oxygen demand), Calcium, Magnesium, Sodium and Potassium. Average results obtained for the two dry seasons for the soil samples around the fish farms showed that: pH 6.33 - 7.24, Organic Carbon 2.03 - 6.00 g/kg, Available Phosphorus 7 - 10 mg/kg, Total Nitrogen 0.95 - 2.10 g/kg, Exchangeable Bases and Exchangeable Acidity 0.02 - 0.06 Cmol/kg were within the permissible limits of FAO and WHO. The various parameters were within the permissible limits for fish production. The fish wastewater had Electrical Conductivity 118 - 230 μS/cm, pH 6.79 - 7.10, and Biological Oxygen Demand 3.0 - 6.0 mg/L. In conclusion, the wastewater from fish farms is good sources of fertiliser to the surrounding farmlands.

Design and performance of a novel rice hydroponic biofilter in a pond-scale aquaponic recirculating system

Aquaponics is the integration of recirculating aquaculture and hydroponic systems which is considered to be an innovative, eco-friendly and sustainable food production technology. In this study, a special design of hydroponic biofilter that integrated constructed wetlands and floating-raft rice hydroponics was constructed to treat the nutrient rich effluents from the intensive fishpond and to establish an aquaponic system on pond scale. The treatment efficiencies and food production potential of the new rice hydroponic biofilter was evaluated after determining the key operating parameters. As the results, overall nutrient removal efficiency was optimized at hydraulic load rate (HLR) of 0.58 m.d−1 and air-to-water ratio of 2:1. The average removal efficiencies of total ammonia nitrogen (TAN), total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand (CODMn) from fishpond wastewater were in the range of 33.75–34.31%, 59.21–64.53%, 68.43–73.75% and 71.66–74.37%, respectively. Meanwhile, hydroponic rice grew well in the biofilter and gained a yield of 7 127 kg.ha−1. These results probably implied that the novel rice hydroponic biofilter exhibited efficient effluent treatment and presented as a viable alternative for the food production in a pond-scale aquaponics recirculating system.

Recycling of fishpond wastewater by adsorption of pollutants using aged refuse as an alternative low-cost adsorbent

Abstract The waste to wealth initiative has been championed by many researchers through the use of waste materials as adsorbents for wastewater treatment. The aged refuse became a research interest due to its availability, low cost and adsorption capacity. The aged refuse used was collected from the Air Hitam Sanitary Landfill site in Selangor, Malaysia which is more than 8 years of placement. The material characterization showed characteristics such as high porosity (51%), bulk density (ρ), 1.23 g cm−3, total surface area (Brunauer–Emmett–Teller) of 3.376 m2 g−I, capacity for exchange of cations and organic content of 9.90% which are ideal conditions for adsorption. The optimized operating conditions during treatment were dosage of 2 g 100 mL−1, pH 6, particle size ≤ 2 mm, agitation speed 250 rpm, and contact time of 70 min. The results showed maximum reduction efficiency of 91% for Chemical oxygen demand, Total suspends solids and Total dissolved solids and 84, 88 and 95% for Biochemical oxygen demand, NH 4 + and Colour respectively and over 60% removal was observed in 10 min. Freundlich model was used to test the experimental data and it gave good correlation with R2 values very close to 1. The aged refuse technology is suitable for wastewater recovery and reuse through innovative column based aged refuse biofilter which incorporates adsorption, filtration, biodegradation and sedimentation processes.

Occurrence of antibiotics and antibiotic resistance genes in soils from wastewater irrigation areas in the Pearl River Delta region, southern China

The occurrence and distribution of tetracycline (TC) and sulfamethazine (SMZ), and the corresponding antibiotic resistance genes (ARGs) were investigated in six agricultural sites in the Pearl River Delta (PRD) region in southern China. Irrigation water and irrigated soils at two different depths (0–10 and 10–20cm) were analyzed. The total concentrations of TC and SMZ in irrigation water ranged from 69.3 to 234ng/L and from 4.00 to 58.2ng/L, respectively, while the total concentrations of TC and SMZ in irrigated soils ranged from 5.00 to 21.9μg/kg and from 1.30 to 4.20μg/kg, respectively. After long-term irrigation with domestic and fishpond wastewater in the field, the residual TC and SMZ and their corresponding ARGs in soils were significantly higher in fishpond-irrigated soils (Dongguan and Shenzhen) than in domestic wastewater-irrigated soils (Foshan, Guangzhou, Huizhou and Zhongshan). The concentrations of antibiotics and their ARGs were significantly higher in irrigation water than in irrigated soils, which indicated that wastewater was the primary source of antibiotics in the soil environments. The domestic and fishpond wastewater were important repositories of antibiotics and their ARGs, which require effective treatment before their discharge into the environment. Other factors such as soil physicochemical properties, manure application, irrigation water sources and cropping patterns also affect the antibiotic concentrations and ARG abundances. The residual antibiotic concentrations statistically correlated with the corresponding ARGs in irrigation water and irrigated soils, both of which decreased with increasing soil depth, indicating that the concentration of antibiotics in the environment exerted a selection pressure on the microorganisms in the environment.

Contribution of basal and aerial tillers to forage production dynamics in Tifton-85 bermudagrass irrigated with fishpond wastewater and fertilized with NPK

This paper aims to assess the contribution of basal and aerial tillers to structural and productive characteristics of Tifton 85 bermudagrass, irrigated with fish tank wastewaters and fertilized with NPK. The experiment was conducted in the city of Petrolina-PE, Northeastern Brazil. The evaluated area had 960 m2 subdivided into five treatments and ten replicates, in a completely randomized design. Treatments consisted of different fertilization rates of NPK (0, 33, 67, 100, and 150%) as recommended by the Handbook of Fertilization Recommendations for the State of Pernambuco, and based on a prior soil analysis. Irrigation water came from fishponds with Nile Tilapia fingerlings. The experiment was divided into four intervals of 27, 29, 18, and 21 days respective to the first, second, third, and fourth cuts. Both tiller types were analyzed for number of individuals, culm length and diameter, fully- and partially-expanded leaves, leaf length and width (fully or partially expanded), dry mass of leaves (fully and partially expanded and total), culm, dead tissue, and total tiller, and the ratio of leaf and culm. Both structural and productive characteristics showed a linear growth trend for both types, with emphasis on the basal tillers. Thus, a suitable supply of nutrients is crucial for grasses, mainly NPK, as these are macronutrients of vital importance in physiological processes. In addition to the nutrients supplied via fish farming wastewater, fertilization with 150% of the recommended amount of NPK promoted a greater structural development of the tillers, increasing their productivity levels.

A novel growth method for diatom algae in aquaculture waste water for natural food development and nutrient removal.

Diatom algae are known to play an important role as primary producers in many diverse ecosystems, including artificial aquaculture ponds where they also aid in maintaining water quality by consuming excess nutrients. But factors influencing their growth are still poorly understood. In the present study the effect of micronutrients, N:P ratio and silica concentration on benthic diatom Synedra sp. grown in fish pond waste water was studied along with nutrient removal efficiency. We have studied nine different treatments, of which addition of micronutrient mixture Nualgi along with adjusted N:P to 6:1 resulted in highest cell density, followed by silicate enrichment, whereas only N:P adjustment and Nualgi addition had no significant effect on diatom growth. At the end of the growth experiment, the N removal efficiencies of treatment groups (50.23%-65.44%) were significantly higher (P < 0.05) than that of the control group (43.56%), whereas phosphate removal efficiency was significantly higher (P < 0.05) with Nualgi and N:P adjustment (53.37%-68.98%). The silicate consumption was significantly higher in the control group, at 63.87%, than in other experimental groups. These results will give us a new insight into important factors influencing beneficial algae growth and simultaneous nutrient removal from aquaculture waste water.

Aged Refuse Characterization as Resource for Wastewater Treatment and Landfill Remediation

Landfilling has become the most effective solid waste disposal option in developing countries. Aged Refuse (AR) in this context is solid wastes from landfill which has become stabilized after several years of placement. The aged refuse sampled from Air Hitam landfill site in Malaysia is characterized as follows: moisture content 29.5%, Loss on Ignition (LOI) 9.90%, porosity 51%, ash content 95.99%, bulk density 1.23 g/cm3, hydraulic conductivity 0.31 cm/min, electrical conductivity 143.10 ms/cm and Carbon-Nitrogen-Sulphur (CNS) of 0.64%, 0.04% and 0.009%, respectively. Cation Exchange Capacity (CEC) is 2.69 meq/100 gm, with exchangeable cations of Calcuim, Magnesium, Potassium and Sodium. The SEM/EDX showed available specific surface area of 3.376 m2/g and negligible heavy metals presence with abundance of Silicon and Oxygen as compounds. The AR texture is similar to loamy clay, with the abundance of microbes at 7.1 × 106 CFU/100 ml, which removed up to 92.1. 88.6, 68.0, 84.7 and 95.1% of COD, turbidity, chromium, NH3-N and colour, respectively from fishpond wastewater.

Comparison of Fish Pond Waste Water with Manures under Garden Egg in Nigeria

&lt;p class="1Body"&gt;Two field experiments were conducted from 2012 to 2013 cropping seasons to evaluate the efficacy and also determine the optimum rates of application for fish pond waste water in comparison with three other manures including one inorganic fertilizer and two organic manures under garden egg (&lt;em&gt;Solanum spp.&lt;/em&gt;) crop.Garden egg was fertilized with pond waste water (PW), poultry manure (PM), pig manure (PG) and NPK15:15:15 at equivalent nitrogen (N) rates (0, 150, 300, 450 kg/ha). The treatments were arranged in a split plot under randomized complete block design (RCBD).The results obtained indicated a slight drop in soil pH but soil OM, total N, available P, exchangeable Ca and K increased generally with increasing rates of manures. The PW and PG treatments supported significantly (P&amp;lt;0.05) the highest yields of the crop compared to PM and NPK with the 150 and 300 kg/ha treatments recording the highest increase. These results have shown that under the high rainfall and acidic soil conditions of Akwa Ibom State in Nigeria, PW is useful for the improvement of soil conditions and achievement of higher crop yields when applied at rates that supply N in the range of 150 – 300 kg/ha.&lt;/p&gt;

Comparative performances of juvenile abalone ( Haliotis tuberculata coccinea Reeve) fed enriched vs non-enriched macroalgae: Effect on growth and body composition

Abalone Haliotis tuberculata coccinea Reeve (1846), is a target species for diversification of European aquaculture production. Taking into account that sustainable, eco-friendly production methods are to be a part of future expansion of the abalone industry, growth performance of juvenile abalone reared in an integrated culture system was evaluated and compared with that of abalone fed non-enriched macroalgae. Four macroalgae treatments, three monospecific: Ulva rigida (UN), Hypnea spinella (HN) and Gracilaria cornea (GN) and a composite one (MN), were produced out of fishpond wastewater effluents, while other four control treatments consisted of the same species reared in fresh seawater (U; H; G; M). Seaweeds reared in fishpond wastewater effluents increased their protein content from 11–17% to 29–34%. Lipids consisted mainly of saturated fatty acids (SFA) (43–60%), palmitic acid being the most abundant fatty acid (40–47%). Highest EPA percentage was found in red algae H. spinella (6.9%), being ten times higher than that of U. rigida (0.7%). All the algae tested contained very low levels of arachinodic acid (0.1–1.6%) and docosahexaenoic acid (0.5–3%). Protein levels in foot muscle (74–76%) did not differ significantly (P < 0.05) among treatments. Survival was generally high, ranging from 85 to 100%. Weight gain (17–561%) and SGR (0.2–2.3%) were positively related to protein content; whereas, protein efficiency ratio (PER) (0.5–3.7) was negative correlated. PE ratios increased by 82–159% (DW) as a function of the enrichment among the different diets. Food conversion ratio (FCR) (7–188) improved according to the increase in PER. Overall, biofilter-produced macroalgae showed a significantly higher dietary value compared to the control treatments. Similarly, animals fed the mixed diets performed significantly better than those fed a single algal diet. Feeding G. cornea led to the lowest growth performance probably due to the lowest feed intake. The results clearly indicate that H. tuberculata coccinea growout can efficiently take place in an integrated-culture system suggesting that on-farm seaweed-abalone production could be part of future development of the abalone industry in the Canary Islands.