Heterotrophic ammonium removal by a novel hatchery isolate Acinetobacter calcoaceticus STB1

► A novel Acinetobacter calcoaceticus strain is proposed. ► The potential use of this strain as a nitrogen balancer is reported. ► This strain shows efficient removal of ammonium at varying concentrations. ► This strain introduces around 22% of ammonium into cell biomass. ► Toxicological studies on Artemia reveal that this strain is non-toxic for nauplii.