To improve total nitrogen removal, a full-scale experimental study was conducted on a hybrid constructed wetlands plant designed for 100 p.e.. The plant composed of a 1st stage of vertical filters (fed with raw wastewater) followed by a 2nd stage of horizontal filters was monitored over one year measuring hydraulic conditions, physico-chemical conditions, gas emission, oxygen of the gas phase and regular treatment performances by 24 h composite samples. Different vertical filter configurations (media depth, intermediate and passive aeration system) were tested as well as two horizontal filter designs. The N removal is discussed on efficiency of each stage in relation to the season and the load applied. This study leads to draw the limit of the plant configuration and gives some design avenues of hybrid systems to reach high and regular level of nitrogen removal with acceptable surface area per person.