Aquaculture equipment provider with Wolize: Shandong Wolize Biotechnology, with 15 years of experience, ISO/CE certifications and university partnerships, designs and delivers turnkey RAS, high-density flow-through and aquaponic systems. Our equipment operates in 47 countries, powering 22 large-scale projects over 3,000 m³ each. We offer design, installation, training and lifelong support, helping farmers triple yield, cut costs 30 % and meet ASC/BAP standards. The Recirculating Aquaculture System (RAS) is a modern aquaculture technology designed to provide a stable and suitable growth environment for aquatic organisms through efficient water treatment and resource recycling. This system is widely applied in various types of aquaculture, including fish, shrimp, and crab farming, and boasts significant environmental, economic, and production advantages. Read extra information on fish farm equipment suppliers.

The development prospects of flow-through aquaculture systems remain very broad. In terms of technological innovation, with continuous advancements in science and technology, new materials, equipment, and technologies will constantly emerge, providing strong support for the upgrading of flow-through aquaculture systems. The application of intelligent equipment will become more widespread, enabling comprehensive real-time monitoring and precise control of the aquaculture environment through sensors, the Internet of Things, and big data technologies. Intelligent feeding systems can automatically adjust the amount and timing of feed based on the growth status and feeding needs of the fish, improving feed utilization and reducing waste. Intelligent water quality monitoring and control systems can promptly detect changes in water quality and automatically activate corresponding treatment equipment to ensure that the water quality is always at its optimal state. This not only improves aquaculture efficiency and product quality but also further reduces labor costs and management difficulty.

Environmental compliance and sustainability are prominent advantages of RAS systems. In traditional pond farming, residual feed and feces are directly discharged, causing eutrophication of surrounding water bodies and ecological pollution. Moreover, the scale of farming is strictly restricted by environmental policies. RAS systems treat farming waste through solid-liquid separation and microbial degradation, achieving zero discharge or resource utilization of pollutants, fully meeting modern environmental protection requirements. In addition, the closed farming model avoids the risk of invasive species and cross-infection of diseases, making product quality easier to control and meeting the demands of food safety.

Flow-rate optimization is an interruption to this dynamic, which causes the hydraulic retention time in each tank or raceway to change. Hydraulic retention time is the time a particle stays in a particular unit before it is forced out (Fan et al., 2023). The shortening of this retention time will allow farms to physically eliminate stages of infective parasites before attaching to fish. The research on monogenean larvae reveals that, they are the most perilous during the initial two hours of their hatching and the infectivity reduces drastically after four to eight hours (Hoai, 2020). In juvenile salmonid or marine finfish systems with retention times in the farms of between thirty and fifty minutes they significantly decrease the likelihood of encountering a host by the larvae. It is an engineering-based solution that is not based on chemicals or biological remedies but rather relies on the velocity of water to exceed the pathogen biological window of infectivity (Morro et al., 2022). When handling highly parasite sensitive species like Atlantic salmon, rainbow trout, cobia, and sea bass, flow-rate manipulation is particularly of particular concern.

Ozone alone cannot maintain a stable RAS environment. Fish release ammonia continuously through their gills and metabolic waste, and even low concentration of ammonia impairs gill function, suppress appetite and inhibit growth. Due to this fact, biological filtration is the second key pillar of the dual-treatment approach. In the biofilter, Nitrosomonas, Nitrobacter and Nitrospira are specific nitrifying bacteria that will turn ammonia to nitrite and subsequently to nitrate via the nitrification process (Oshiki et al., 2022). This bio-chemical conversion is necessary in preserving a safe environment in high-density aquaculture plants. Due to ozone being sensitive to these bacteria, physical separation between ozone contact and biological filtration must be maintained during system design. In contemporary RAS, ozone is sprayed into a separate chamber where it combines with water then flows through a degassing unit that removes all the remaining ozone. This step is only done after which treated water can be admitted into the biological filtration process(Xiao et al., 2019).

Against the backdrop of a growing global population and increasingly strained wild fishery resources, aquaculture has become a key industry for ensuring protein supply security. However, traditional aquaculture models often come with environmental pressures, high consumption of land and water resources, and the risk of disease transmission. Within this global context, the African continent stands at a historic crossroads. It boasts vast coastlines and abundant water bodies, yet simultaneously faces severe challenges related to food security, water scarcity, and climate change. It is precisely within this complex scenario that a revolutionary technology known as Recirculating Aquaculture Systems (RAS) is quietly emerging in Africa, heralding a silent yet profound transformation for the continent’s aquaculture sector. Discover extra info at wolize.com.