In brief, the
system consisted of three stages of constructed wetlands (Fig. 1).
The first one was operated as saturated vertical flow unit; the saturation
was created by a standpipe which kept the water level
about 5 cm below the filter surface. The second stage was a “typical”
vertical flow unit with free drain and the last stage consisted
of a horizontal subsurface flow unit. The vertical flow units were
planted with Common reed (Phragmites australis), horizontal flow
unit was planted with Reed canarygrass (Phalaris arundinacea)
(Supplementary Material S6 and S7).