Phytoremediation Potential of Selected Plants & Growth of Oreochromis niloticus (Linnaeus, 1758) in Aquaponic Systems

Aquaponic systems use plants` natural ability to absorb nutrients from aquaculture wastewater. This improves water quality for fish and promotes plant growth, resulting in a sustainable and efficient food production method. However, the nutrient removal capacity of many plant species within aquaponics remains underexplored. This study investigated the potential of three plant species: sweet wormwood (Artemisia annua), pumpkin (Cucurbita pepo) and amaranth (Amaranthus dubius) for biofiltration within a media-based aquaponic system. In addition, the growth performance of plants and Nile tilapia (Oreochromis niloticus) within the system was evaluated. Artemisia annua recorded significantly higher removal rates for ammonia (52.5 ± 19.9%), nitrate (61.6 ± 9.02%), and nitrite (41.9 ± 8.7%) compared to other plant species. In contrast, C. pepo exhibited the lowest nutrient removal efficiency. Most water quality parameters, except for ammonia and dissolved oxygen, remained within the optimal range for O. niloticus growth during the experiment. Significantly higher (P˂0.05) fish growth rates (0.33 ± 0.006 g/day) were observed in A. annua than other treatments. Similarly, A. annua produced the highest plant yield (0.49 ± 0.02 kg/m²), while C. pepo yielded the least (0.29 ± 0.00 kg/m²). All the studied plants reduced aquaponic system waste, with A. annua exhibiting significantly higher biofiltration efficiency, promoting increased fish growth and plant yield. This demonstrates their potential for sustainable aquaculture through wastewater treatment and healthy fish production in media-based systems.