For G. chorda, the NH4+ biofiltering efficiency was higher than the NO3– + NO2– biofiltering efficiency (Table 1). In contrast, S. japonica showed the highest NO3– + NO2– biofiltering efficiency (65.2%) at the end of the experiment. The PO43– biofiltering efficiencies of the three species were lower than the total nitrogen efficiency. After seven days, the PO43– biofiltering efficiency ranged from 38% for G. chorda to 20.2% for S. japonica.