Assessing the Role of Native Aquatic Plants in Maintaining Water Quality in Integrated Fish Farming Systems: A Quantitative Evidence Synthesis

The intensive pond farming system loses most of the feed's nitrogen and phosphorus content as dissolved and particulate nutrients, causing eutrophication that can be dangerous to the farm itself and the receiving water body. Using native aquatic plants has been suggested as an economic natural method to help mitigate the problem, but information is scattered over different species, sizes and systems. The current study summarises the nine-research works conducted between 2020 and 2025 on the effectiveness of the use of floating, submerged and emergent macrophytes, and rice floating beds in lab tanks, ponds and commercial scale wetlands. Removal efficiency was 50–98%, 64–98% and 73–98% in 14 days for phosphate, ammonia-nitrogen and suspended solids, respectively. The commercial scale wetland was able to remove 25–44% and 62–72% of total nitrogen and total phosphorus, respectively. Submerged macrophytes retained 75% less total phosphorus than control sites after 90 days in pond studies, and avoided cyanobacteria blooms, while rice-fish farming reduced phosphorus mobilization from sediments by 82%. It varied according to the species used, the season, dissolved oxygen levels, retention time and biomass harvesting. There were several successful species that were invasive in non-native regions, and only occasionally is their nativeness noted. The provided block diagram for plant-based treatment trains, a decision matrix for species selection, and research needs for incorporating native plants into fish farms.