The
nutrient-assimilating photoautotrophic plants can be used
to turn nutrient-rich effluents into profitable resources
(Neori et al., 2004). Biofiltration by plants generates in the
culture system a mini-ecosystem, in which, if properly
balanced, plant autotrophy counters fish (or shrimp) and
microbial heterotrophy, not only regarding nutrients but
also with respect to oxygen, pH and CO2