This is the first granulation study except Ferguson [Ferguson LN. Anaerobic codigestion of aircraft deicing fluid and microaerobic studies. M.S. Thesis. Milwaukee, WI, USA: Marquette University; 19991 to develop coupled granules by using a mixture of suspended anaerobic and aerobic cultures exposed to alternating cyclic anaerobic/microaerobic/aerobic conditions. Coupled granules with median sizes of 1.28-1.86 mm and settling velocities of 31-39 m/h were developed, which were comparable to those of both anaerobic and aerobic granules. Coupled granules displayed noteworthy specific methanogenic activity (SMA) and specific oxygen uptake rate (SOUR) as 14-42 mL CH4/g VSS h h and 6-47 mg DO/g VSS h, respectively, indicating that they were composed of both anaerobic and aerobic cultures. (c) 2005 Elsevier Ltd. All rights reserved.