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Some studies have reported the removal of As (As) and fluoride (F - ) using different sacrificial anodes; however, they have been tested with a synthetic solution in a batch system without hydrated silica (SiO 2 ) interaction. Due to the above, concurrent removal of As, F - , and SiO 2 from natural deep well water was evaluated (initial concentration: 35.5 μg L -1 As, 1.1 mg L -1 F - , 147 mg L -1 SiO 2 , pH 8.6, and conductivity 1024 μS cm -1 ), by electrocoagulation (EC) process in continuous mode comparing three different configurations of sacrificial anodes (Al, Fe, and Al-Fe). EC was performed in a new reactor equipped with a small flow distributor and turbulence promoter at the entrance of the first channel to homogenize the flow. The best removal was found at j = 5 mA cm -2 and u = 1.3 cm s -1 , obtaining arsenic residual concentrations (C As ) of 1.33, 0.45, and 0.77 μg L -1 , fluoride residual concentration ( [Formula: see text] ) of 0.221, 0.495, and 0.622 mg L -1 , and hydrated silica residual concentration ( [Formula: see text] ) of 21, 34, and 56 mg L -1 , with costs of approximately 0.304, 0.198, and 0.228 USD m -3 for the Al, Fe and Al-Fe anodes, respectively. Al anode outperforms Fe and Al-Fe anodes in concurrently removing As, F - and SiO 2 . The residual concentrations of As and F - complied with the recommendations of the World Health Organization (WHO) (As < 10 μg L -1 and F -  < 1 mg L -1 ). The spectroscopic analyses of the Al, Fe, and Al-Fe aggregates showed the formation of aluminosilicates, iron oxyhydroxides and oxides, and calcium and sodium silicates involved in removing As, F - , and SiO 2 . It is concluded that Al would serve as the most suitable sacrificial anode., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)