Wastewater treatment by membrane processes requires at least 3 different membranes with performances falling in the microfiltration, ultrafiltration and nanofiltration ranges. Often, the composition of these membranes varies, and their preparation processes may involve several steps and lengthy or costly post-treatment procedures, for instance to endow the membrane with fouling-resistance property. Here, we intended to explore potential routes to simplify the treatment process. We solely used one single casting solution with the purpose of preparing 3 membranes without any post-treatment, that were then implemented in a 3-stage filtration process. This solution contains polyvinylidene fluoride (PVDF), a copolymer of styrene and polyethylene glycol methyl ether methacrylate (PS-r-PEGMA), and a solvent. 3 phase inversion processes: vapor-induced phase separation (VIPS), liquid-induced phase separation (LIPS) and evaporation-induced phase separation (EIPS) were executed to reach the desired membrane properties. Careful examination of the membrane structure, physical properties and permeability prove that the membranes prepared by VIPS (pore size: 0.4–0.8 µm), LIPS (pore size: 0.008–0.09 µm) and a combination of EIPS and LIPS (pore size: 3–6 nm) were suitable for the rejection of large biofoulants such as microalgae, large and small proteins, respectively, despite the presence of the antifouling copolymer that affected the membrane structure. Next, the 3 membranes were used to treat synthetic wastewater containing a mixture of microalgae, bovine serum albumin (BSA) and lysozyme. The first filtration stage permitted to reject almost entirely the Microalgae (99.3–99.5% rejection), the second filtration stage then removed larger proteins (cumulated “Microalgae/protein” rejection of about 93%) while the last stage rejected a large quantity of the smaller protein. The copolymer was also shown to reduce fouling by a 5-fold factor. Hence, this work demonstrates that a complete set of pressure-driven antifouling membranes for full wastewater treatment may be prepared from one single formulation and by phase inversion only.