CANON was successfully developed in a continuous reactor with nitritation granules as inoculum. Superior TN removal rate of 2.83 kg N m−3 d−1 was achieved at hydraulic retention time of 0.9 h. Improvement of specific TN removal rate was positive related to the EPS accumulation. High-throughput pyrosequencing showed a co-culture of Nitrosomonas and Candidatus Kuenenia.