The remaining phosphorus and system pH of the solution
during the 5 cycles of the experiment is shown in Fig. 1. N. nucifera
and C. alternifolius still had high phosphorus removal efficiency
and could survive in the wetland system after 5 cycles of the
experiment. After 5 cycles of experiment, plants look healthy and
no toxic symptom appeared. It was possible to add the wastewater
for the next cycle experiment. During 5 cycles, the plant took 5
days per each cycle to remove phosphorus from wastewater to less