Sustainable　partial　nitrification　to　nitrite　has　been　proven　difficult　in　treating　low　strength　nitrogenous　wastewater.　Real-time　aeration　duration　control　was　used　to　achieve　efficient　partial　nitrification　to　nitrite　in　a　sequencing　batch　reactor　(SBR)　to　treat　low　strength　domestic　wastewater.　Above　95%　nitrite　accumulation　ratio　was　maintained　for　long-term　operation　at　normal　condition.　Partial　nitrification　established　by　controlling　aeration　duration　showed　good　performance　and　robustness　even　though　some　time　encountering　long-term　extended　aeration.　Process　control　enhanced　the　successful　accumulation　of　ammonia　oxidizing　bacteria　(AOB)　and　washout　of　nitrite　oxidizing　bacteria　(NOB).