Optimal phosphate concentration for growth and normal functioning of the marine anammox bacteria, Candidatus Scalindua sp.

The anammox process using marine anammox bacteria is a promising nitrogen removal process for recirculating aquaculture system wastewater. Marine anammox bacteria are typically found in oxygen-deficient zones and coastal areas under low phosphate concentrations. The optimal phosphate concentration for marine anammox bacteria remains still unknown because most laboratories studies of these bacteria have been conducted under high phosphate concentrations. This study investigated the long-term effects of varying phosphate concentrations on the marine anammox bacterium, Candidatus Scalindua sp., to determine the optimal range of phosphate. Anammox activity and growth rates were evaluated under seven phosphate concentrations (0, 0.23, 0.46, 0.68, 1.14, 6.15 (control), and 15.48 mg-P L-1) over a period of 70 days.