ET decreases the amount of treated wastewater available at outflow of a CW system.

When ET strongly increases, an apparent decrease of RE on organic compounds can be expected in a CW system.

For the pollutant removal efficiency of the system, mass loads calculation provides more informative than pollutant concentration in a CW system.

ET rates and K_c values of plant species have to be considered when designing a CW system.

Typha latifolia consumes more water than Cyperus alternifolius but more efficiently under Mediterranean climatic conditions.