scholarly journals WATER QUALITY AND WASTE CONTAMINATION STUDY IN CATFISH REARING RECIRCULATING AQUACULTURE SYSTEM

Author(s):  
Gražina ŽIBIENĖ ◽  
Alvydas ŽIBAS

In this article we analyse catfish rearing conditions in recirculating aquaculture systems (RAS). Based on research, performed by scientists from different countries, we evaluated optimal water parameter values for catfish rearing. African catfish growing process and with it associated factors were researched in JC ,,Šamas“. The amount of dissolved oxygen (on average 4,53 mg/l) in the rearing basin is adequate for the catfish to feel comfortable and for biomass growth. Water temperature only varies slightly – the average water temperature is 23,30C. The ideal pH for rearing fish in RAS is 7.0. Many aquaculture species continue to feel comfortable in pH boundaries of 6.5-8.5. In the samples, taken from catfish rearing system, the pH varied from 5.58 to 6.63. Such acidic water decreases the effectiveness of biological filter, but also decreases the toxic effect of excreted ammonia on the fish. Only a small amount of suspended solid is present in the samples, which means that they are being removed properly. The average amount of ammonia nitrogen in the water basins in analysed catfish rearing systems is 1,171 mg/l. The analysed water samples presented an average nitrite amount of 0,974 mg/l. The recommended amount of nitrites for catfish is less than 0.5 mg/l. The analysed samples presented relatively high nitrate values – from 412 to 495 mg/l. In order to decrease the concentration of accumulated nitrates it is required to change no less than 10% of total system water volume every day. The index of consumed biochemical oxygen corresponds to the requirements for water quality in RAS

2020 ◽  
Vol 12 ◽  
pp. 251-262
Author(s):  
Y Shao ◽  
H Zhong ◽  
X Mao ◽  
H Zhang

The frequency of water exchange and reducing the risk of eutrophication to surrounding water bodies have always been water-quality control issues in recirculating aquaculture systems. In this study, maize straw biochar prepared through pyrolysis showed great potential for both bacterial immobilization and pollutant adsorption. Heterotrophic bacterial strains of Sphingomonas sp. PDD-57b-25 and Acinetobacter towneri were isolated in situ from wastewater for pollutant remediation through a 16S rDNA-based method, which has been rarely reported to date. The selected strains had higher ammonia nitrogen (NH4+-N, 63%), nitrite nitrogen (NO2--N, 38%), nitrate nitrogen (NO3--N, 25%) and total phosphorus (TP, 35%) assimilation capacities than those of other widely applied bacteria under similar medium conditions. In addition, more NH4+-N (+16%), NO2--N (+14%), NO3--N (+17%) and TP (+19%) was removed by biochar-immobilized isolated strains than dissociated strains, suggesting their use may provide a means of improving water-quality control in recirculating aquaculture. With specific additions (4 g l-1) of biochar-immobilized Sphingomonas sp. PDD-57b-25 and A. towneri, the dissolved inorganic nitrogen (approximately 0.45 mg l-1) and TP (approximately 0.09 mg l-1) levels were maintained below the clean water threshold for recirculating aquaculture of crab Eriocheir sinensis. Furthermore, the added strains exhibited high bio-safety and were capable of improving the yield and quality of crabs. Results indicate the potential applicability of biochar-immobilized Sphingomonas sp. PDD-57b-25 and A. towneri in agricultural sewage treatments. Further, the experimental methodology developed here may be used for the exploration of new strains for practical aquaculture.


2015 ◽  
Vol 65 ◽  
pp. 17-26 ◽  
Author(s):  
Paulo Fernandes ◽  
Lars-Flemming Pedersen ◽  
Per Bovbjerg Pedersen

2021 ◽  
Vol 21 (7) ◽  
pp. 3975-3979
Author(s):  
Min-Jin Hwang ◽  
Jeongmin Cha ◽  
Eun-Sik Kim

In a fish farm, the water quality is important to ensure fish growth and farm productivity. However, the study of the quality of water using in aquaculture has been ignored until now. Although there are several methods to treat water, nanomaterials have not yet been applied for indoor fish farming because it may difficult to supply a sufficient amount of water, and the operating parameters have not been developed for recirculating aquaculture systems. Nanotechnology can be applied to treat water, specifically through adsorption and filtration, to produce drinking water from surface water and to treat wastewater by processing a high volume of effluent. The adsorption and filtration of seawater has also progressed to allow for desalination of seawater, and this is recognized as a necessary tool for extended treatment protocols of various types of seawater. This study investigated the treatment of aquaculture water using nano-porous adsorbents (e.g., pumice stone) to control the contaminants in seawater in order to maintain the water quality required for aquaculture. The results are used to derive an analytical relationship between the ionic species in aquaculture water, and this provides empirical parameters for a batch reactor for aquaculture. The quality of the influent and effluent for aquaculture is compared using time-series analyses to evaluate the reduction rate of ionic components and thus suggest the optimum condition for fish farming using bioreactor processes.


2021 ◽  
Vol 21 (3) ◽  
pp. 93-100
Author(s):  
Arning Wilujeng Ekawati ◽  
Siti Mariyah Ulfa ◽  
Citra Satrya Utama Dewi ◽  
Abdul Aziz Amin ◽  
Lutfi Ni’matus Salamah ◽  
...  

Water quality and waste management are significant problems for aquaculture in Indonesia, including catfish (Clarias gariepinus) aquaculture. A combination of Aquaponics Systems and Recirculating Aquaculture Systems (A-RAS) has been developed to address this problem. This study analyzed A-RAS application for catfish (Clarias gariepinus) aquaculture by comparing water quality and production indicators between A-RAS and conventional methods. The results show that temperature, pH, dissolved oxygen, total organic matter, ammonia, nitrate and nitrite in A-RAS technology were 28.0-30.0°C, 6.5-7.9, 3.8-7.8 mg/L, 18.54-24.97 mg/L, 0.12- 0.28 mg/L, 0.12-0.13 mg/L, and 0.04-0.13 mg/L, respectively. Survival Rate, Feed Conversion Ratio, and harvest in A-RAS application were 85.5%, 1.1, and 26 kg/m³, respectively. A-RAS technology can maintain water quality to be reused in cultivation and increase yields by about 13%. Besides, water spinach can be an additional income for farmers.


2018 ◽  
Vol 133 ◽  
pp. 289-298 ◽  
Author(s):  
Aikaterini Spiliotopoulou ◽  
Paula Rojas-Tirado ◽  
Ravi K. Chhetri ◽  
Kamilla M.S. Kaarsholm ◽  
Richard Martin ◽  
...  

Author(s):  
Carlos A. Espinal ◽  
Daniel Matulić

AbstractRecirculating aquaculture technology, which includes aquaponics, has been under development for the past 40 years from a combination of technologies derived from the wastewater treatment and aquaculture sectors. Until recently, recirculating aquaculture systems (RAS) farms have been relatively small compared with other types of modern aquaculture production. The last two decades have seen a significant increase in the development of this technology, with increased market acceptance and scale. This chapter provides a brief overview of the history, water quality control processes, new developments and ongoing challenges of RAS.


Antibiotics ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 192 ◽  
Author(s):  
Gabriel M.F. Almeida ◽  
Kati Mäkelä ◽  
Elina Laanto ◽  
Jani Pulkkinen ◽  
Jouni Vielma ◽  
...  

Aquaculture production has increased tremendously during the last decades, and new techniques have been developed, e.g., recirculating aquaculture systems (RAS). In RAS, the majority of water volume is circulated via mechanical and biological filters and reused in the tanks. However, the prevention and treatment of diseases in these systems are challenging, as the pathogens spread throughout the system, and the addition of chemicals and antibiotics disrupts the microbiome of the biofilters. The increasing antibiotic resistance has made phage therapy a relevant alternative for antibiotics in food production. Indeed, as host-specific and self-replicating agent they might be optimal for targeted pathogen eradication in RAS. We tested the survival and spread of Flavobacterium columnare -infecting phage FCL-2 in recirculating aquaculture fish farm with rainbow trout (Oncorhynchus mykiss) in a fully controlled study. After a single addition, phage persisted in water samples collected from tank, fixed bed, moving bed, and aeration unit up to 14 days, and in the water of rearing tanks, rainbow trout mucus, and bioreactor carrier media from the fixed and moving bed biofilters for 21 days. Furthermore, phage adsorbed preferentially to moving bed carrier media, which contained biofilm attached and from which higher phage numbers were recovered. This study shows phages as a potent strategy for maintaining biosecurity in RAS systems.


2015 ◽  
Vol 6 (3) ◽  
pp. 544-560 ◽  
Author(s):  
Manuel C. Almeida ◽  
Pedro S. Coelho ◽  
António C. Rodrigues ◽  
Paulo A. Diogo ◽  
Rita Maurício ◽  
...  

Changes in water temperature and stratification dynamics can have a significant effect on hydrodynamics and water quality in reservoirs. Therefore, to assess future climate impacts, projections of three regional climate models for Europe, under the IPCC A1B emission scenario (2081–2100), were used with the CE-QUAL-W2 water quality model to evaluate changes in the thermal regime of 24 Portuguese reservoirs, representing different geographic regions, morphologies, volumes and hydrological regimes. Simulation results were compared with reference simulations for the period 1989–2008 and changes in water temperature and thermal stratification characteristics were evaluated. Future inflow scenarios were estimated from precipitation-runoff non-linear correlations and outflows were estimated considering present water uses, including hydropower, water supply and irrigation. Results suggest a significant increment in the mean water temperature of the reservoirs for the entire water volume and at water surface of 2.3 and 2.5 °C, respectively, associated with a runoff reduction of approximately 23%. Overall, variations in annual stratification patterns are characterized by changes in the mean annual length of stratification anomaly that ranged from −21 to +39 days. Results also show the influence of depth and volume over the reservoir's temperature anomaly, highlighting the importance of future water uses and operation rule curves optimization for reservoirs.


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