The treatment as been done using a sequence of aeration and non-aeration periods. Test were done to verify the effect of the aeration – non-aeration period to find the optimal combination as limiting aeration result in a reduction in the energy consumption. Based on the result the anoxic (without aeration) period should not exceed 8 hours between fill and react sequences as the sludge settling process deteriorate and odour emissions can be a problem. This study showed that the air supply could be reduced by 42% without affecting the performances. No statistical analysis of the results is presented so it is difficult to evaluate if the difference between the tests done are significant.