Scientific Reports of the National University of Life and Environmental Sciences of Ukraine

Optimisation of biofiltration in closed aquatic systems for the sustainable development of aquaculture: Environmental aspects and technological innovations

Artem Kravchenko*

a-kravchenko05@outlook.com

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Abstract

The aim of the study was to establish the theoretical and applied foundations for optimising biofiltration in closed-loop aquaculture water systems, taking into account environmental requirements, technological innovations and the stability of biofilter operation. The study was conducted within a theoretical and applied framework, utilising scientific analysis, biochemical generalisation, comparative technological analysis, ecological generalisation and the systematisation of current data on biological water treatment. It was established that biofiltration ensured the conversion of ammonium nitrogen, nitrites, and nitrates through the sequential action of bacterial and archaeal communities, and that its stability was determined by temperature, pH, alkalinity, dissolved oxygen, salinity, organic load and the condition of the biofilm. Six main groups of aquatic pollutants, nine biofilter control parameters, seven biofiltration process options, six environmental effects and six innovative areas for optimisation were systematised. A review of the literature showed that the choice of biofilter type should depend on the nitrogen load, salinity, the need for CO₂ degassing, the level of automation and the complexity of operation. Reactors with a moving biofilm bed are suitable for intensive recirculating aquaculture systems (RAS), denitrification modules are suitable for controlling nitrate accumulation, and combined treatment is suitable for comprehensive water quality management. Design improvements, sensor monitoring, automated control and predictive models enhance the manageability of the nitrogen cycle and reduce the risk of toxic compound accumulation. It has been demonstrated that biofiltration helps to reduce the need for water exchange, limit contaminated effluent, minimise the risk of eutrophication and improve the efficiency of aquatic bioresource utilisation. The practical significance of the results lies in the fact that these results can be used by engineers at aquaculture enterprises, environmentalists, designers of closed-loop aquatic systems and specialists at fish farms to select the type of biofilter, set up water quality monitoring and reduce the environmental impact of production

Keywords

alkalinity; dissolved oxygen; nitrates; denitrification modules; toxic compounds

Suggested citation
Kravchenko, A. (2026). Optimisation of biofiltration in closed aquatic systems for the sustainable development of aquaculture: Environmental aspects and technological innovations. Scientific Reports of the National University of Life and Environmental Sciences of Ukraine, 22(4),178-193. https://doi.org/10.31548/dopovidi/4.2026.178
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