Inorganic nitrogen dynamics in sequencing batch reactors using biofloc technology to treat aquaculture sludge

► Focused on inorganic nitrogen syndrome in SBR using BFT to treat aquaculture sludge. ► Ammonium decreased from 13.22 ± 0.98 mg N/L to 0.40 ± 0.02 mg N/L within 6 h. ► Nitrate decreased from 72.41 ± 1.34 mg N/L to 0.10 ± 0.02 mg N/L with 5 h. ► Nitrification progress was observed during start-up of reactors.