Posted by Amelia Whitehart on December 5, 2025 in Agriculture
Aquaculture equipment manufacturer in China: In terms of water resource utilization, RAS systems demonstrate an extremely water-saving characteristic. Traditional pond farming relies on natural water sources for replenishment, with each pond requiring hundreds of cubic meters of water for each water change, and is significantly restricted by water quality and seasonal changes. In contrast, RAS systems achieve over 90% water recycling through physical filtration and biological purification, only requiring a small amount of new water to make up for evaporation and waste discharge, resulting in a water-saving rate of over 95%. This advantage is particularly prominent in areas with water shortages, as it breaks the dependence on natural water sources and reduces water extraction costs.
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. Discover more details on fish farming supplies manufacturer.
UV performance depends heavily on system design. Undersized sterilizers allow partial bypass, leaving incoming pathogens untreated (Summerfelt, 2003). UV efficiency drops significantly in water with turbidity greater than five NTU, suspended solids above 25 mg/L, or UV transmittance lower than 85% (Desmi, 2025). For this reason, large-scale operations typically place mechanical drum filtration before UV chambers to remove particulates that would otherwise block light penetration. Many commercial aquaculture facilities install redundant UV banks to ensure uninterrupted disinfection even when lamps require maintenance or experience unexpected failure (Li et al., 2023). The dual ozone-biofilter system does not only favor the quality of water, but also the sustainability of the entire farm. Disease-free conditions reduce the usage of antibiotics and minimize losses in operations. Constant water quality enhances efficiency of feed-conversion, growth rates and predictability of harvest. As pressures mount on the world aquaculture to produce high quality seafoods with minimum effect on the environment, zero-outbreak RAS operations are a feasible way forward to sustainable intensification.
To ensure the success of the dual ozone-biofilter system, it is important to maintain the right operation parameters. The values of oxidation-reduction potential in the ozone contact chamber are normally 275 to 320 millivolts (mV). This spectrum aids in efficient reduction of organic matter without generating any undesirable reaction byproducts (Davidson et al., 2021). Before the ozone unit, mechanical drum filters of sixty to one hundred microns in size are used to remove large, suspended solids to enhance ozone efficiency by decreasing the organic load. Optimal values of dissolved organic carbon are four milligrams per liter because beyond this level, the water fails to be clear and promotes the growth of microbes. The concentration of dissolved oxygen below the ozone chamber is usually more than nine milligrams per liter since ozone decomposes naturally to produce oxygen. Having high dissolved oxygen levels greatly improves fish metabolism as well as the rate of nitrification. Most importantly, the amount of residual ozone entering the biofilter should also be zero, this is achieved through constant monitoring to ensure that the nitrifying bacteria is not damaged.
The significant increase in unit output efficiency greatly enhances economic benefits. Traditional pond farming has a low density, with an average yield of only a few hundred kilograms per mu, and is limited by land area in terms of large-scale expansion. RAS systems can increase space utilization through three-dimensional farming and multi-layer layouts, with a farming density 5 to 10 times higher than that of ponds, and an equivalent yield of several thousand kilograms per mu. At the same time, precise feeding and stable environmental conditions reduce feed waste and disease losses, increasing the feed conversion rate by 15% to 25% compared to traditional methods, significantly reducing the production cost per unit product. Export potential will expand as West African producers meet global standards for quality and sustainability, tapping into European and global markets hungry for responsibly sourced seafood. Find additional details on https://www.wolize.com/.
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.