Microalgae are considered a rising biomass feedstock that can produce a wide range of biofuels—including biodiesel, bioethanol, biogas, and bio-oil—as well as high-value products such as fertilizers, nutraceuticals, and aquaculture feed. However, conventional suspended algal cultivation systems face some challenges due to low cell densities and costly harvesting processes, which can account for up to 30% of total production costs. As an alternative to conventional methods, biofilm-based systems such as Revolving Algal Biofilm (RAB; Figure 1) offer significant advantages by enabling algae to grow attached to surfaces, allowing for easier and more cost-effective biomass harvesting. The integration of microalgae through the state-of-the-art RAB units in a Recirculating Aquaculture System (RAS) can be a promising approach to improve the stability of water quality and control harmful bacteria in the culture water. Hence, the goal of this study is to evaluate the effectiveness of integrating the RAB unit in RAS and its impact on nutrient removal, algal biomass production, and overall system performance. This ongoing experiment is evaluating the integration of coupled and decoupled RAB into RAS to optimize not only water quality conditions but also the quality of algal biomass produced. This experiment involves four treatments (control, RAB coupled, RAB decoupled, suspended algae), with three replicated systems per treatment. Each of the twelve systems has a total water volume of approximately 375 L and consists of a 113.6-L fish tank, a settling chamber (radial flow filter), a RAB unit installed post-tank for nutrient assimilation, biological filtration for nitrification, and a sump (Figure 2). Tilapia (Oreochromis niloticus) are stocked at an initial density of approximately 20 kg/m³, with 18 fish per system having an average initial weight of 2.55 ± 0.07 kg. The algae species Chlorella vulgaris is being used to assimilate nitrogenous waste and convert it into value-added products, including proteins, pigments, and polyunsaturated fatty acids. Water quality parameters—ammonia, nitrite, nitrate, potassium, iron, magnesium, calcium, and phosphate—are monitored two times a week, while dissolved oxygen, temperature, and pH are measured twice daily. Fish are fed with a formulated diet by Cargill Animal Nutrition (Triton transition, Minneapolis, MN, USA) throughout the experiment. At the end of the study, fish growth performance, algal biomass yield, and the nutritional composition of algae will be analyzed across all treatments.