Phosphorus removal in vertical flow constructed wetlands is very limited, and it is not possible to obtain a sand bed medium that has a sufficient high capacity to bind phosphorus for a prolonged period (Arias et al., 2001, Del Bubba et al., 2003 and Arias and Brix, 2005). Therefore, the phosphorus binding capacities of various artificial media have been assessed in the laboratory in an attempt to find a medium that could be used to bind phosphorus. The idea was to establish a separate exchangeable filter unit after the constructed wetland system to remove phosphorus from the effluent (Brix et al., 2001 and Arias et al., 2003a). A suitable calcite material was identified, but the full-scale tests showed that removal initially was good, but after a few months, the filters were saturated with phosphorus and there were problems with clogging. It has not subsequently been possible to solve the inherent problems with this material. Instead phosphorus removal can be obtained by simple precipitation with an aluminium compound in the sedimentation tank prior to the wetland.