The intensification in aquaculture production leads to increasing attention on the management of ammonia from its waste. Natural solutions such as Yucca schidigera extracts have shown beneficial effects. Their origin (harvested from the wild), however, call for alternative and equally efficient solutions in order to increase the sustainability of their production. In this work, juvenile Nile tilapias (Oreochromis niloticus) were supplemented with different doses of a commercial mixture of saponin-rich plants (Norponin® OPTI, CTL: 0ppm, D1: 100ppm, D2: 500ppm and D3: 2500ppm). The impact on water quality was monitored, with a particular attention to total ammonia excretion (TAN). TAN was significantly reduced in treatments D1 and D2 compared to the control and D3 treatments (p<0.05). Overall, the present study demonstrates that a supplementation with low doses of the feed additive (100 or 500ppm) induced beneficial effects on TAN management.