Tilapia aquaculture has become a main contributor to Brazil’s aquaculture, particularly based on grow-out operations within floating cages sited hydroelectric reservoirs and earthern ponds . Plastics play a important role in optimizing these aquaculture systems, addressing various challenges and enhancing overall efficiency. This study provides an overview of plastic applications in tilapia aquaculture, focusing specifically on their utilization in hydroelectric reservoirs and earthen ponds in Brazil, as these modalities includes more than 90% of Brazilian aquaculture production . Four tilapia cage farms in hydroelectric reservoirs were visited, all located in the Tietê River basin, in the Upper Paraná River region, southeastern Brazil, as well as two tilapia fingerling producers. Five tilapia grow out farms in earthen ponds were also visited, all located in the western region of Paraná state, in the southern region of Brazil. I nterviews were conducted with the farm operators to detail quantitative aspects of plastic use, and destinations after use. Subsequently, the farm facilities were visited to record the types of plastics present and to collect materials for the identification of plastics used. Floating devices made from recycled high-density polyethylene (HDPE) cylindrical containers, with capacities ranging from 30 to 50 liters, are widely used, although floats made of polyvinyl chloride (PVC), specifically manufactured for this purpose, are also used. The floating structures are anchored with polyethylene (blue) and polypropylene (white) rope s, and m etal meshes of the cages are often coated with PVC . Other plastic uses in this type of cage culture include poliamide nets for fish harvesting , internal structures for feed retention made of PVC, anti-bird screens made of polyethylene filaments. Polyester filaments coated with PVC also used in many other devices for fish manipulation. Juveniles are transported in polyester (fiberglass) tanks installed on trucks and, less frequently, in transparent polyethylene bags. For earthen ponds , it is not common to use geomembranes covering the entire bottom of the tank, but HDPE and PVC membranes are used to prevent erosion by lining the tank edges. HDPE is commonly used for aerators and automatic feeders, with internal hard parts of nylon for greater durability. Water conduits are often made of PVC, although HDPE also be used. Similarly, to cage aquaculture, a variety of plastic materials are used in fish handling and harvesting. Fingerling production tanks visited are placed in greenhouses, with a diverse array of plastic equipment used for water treatment and fish manipulations. Plastics are extensively employed for tilapia farming, offering durability, flexibility, and resistance to harsh environmental conditions prevalent in these settings. P lastics are very important in the establishment of infrastructure for tilapia production in earthen ponds , including tank liners, water pumping systems, filters and aeration devices, used for water management and fish husbandry practices. Ongoing research efforts focus on developing rational plastic alternatives to promote sustainable plastic usage in tilapia aquaculture, thereby supporting the long-term viability of aquaculture operations.