The main goal of the current studies was to cultivate granular sludge in a continuous flow membrane bioreactor (CFMBR) to enhance the membrane performance in a pilot-scale reactor. In this regard, CFMBR was operated in two stages for 220 days; stage 1 was run without the addition of aerobic granules, while in stage 2, the aerobic granules synthesized (after a period of regulations) in a granular sludge sequencing batch reactor were seeded in the reactor. The results showed that the particle size in stage 2 was increased to nearly 625 mu m and SVI5 decreased to 45 mL/g from that of 200 um and 145 mL/g, respectively, during stage 1. The membrane fouling noted in terms of increase in transmembrane pressure values in CFMBR stage 2 was approximately 8 times lower than that of stage 1 of operation. Membrane cleaning was a regular phenomenon in stage 1, whereas no cleaning was needed during stage 2. The physicochemical analysis showed that a high PN/PS ratio (3.30) of the EPS, approximately 4-fold low soluble microbial products, a high particle size and sludge settleability were the main factors in mitigating this membrane fouling. The characterization of membrane foulants was done using FTIR spectroscopic technique. (C) 2015 Elsevier B.V. All rights reserved.