Removal of copper (Cu), chromium (Cr) and nickel (Ni) from metal plating wastewater by electrocoagulation with iron and aluminum electrodes with monopolar configurations was investigated. The influence of electrode material, current density, wastewater pH and conductivity on removal performance was explored. The results showed that metal removal increased with increasing current density, pH and conductivity. The efficiency of different electrode materials (iron, aluminum) was compared. The results indicated that electrocoagulation with an Fe-Al electrode pair was very efficient and was able to achieve 100% Cu, 100% Cr and 100% Ni removal at an electrocoagulation time of 20 min, a current density of 10 mA/cm(2) and a pH of 3.0. Corresponding energy and electrode consumptions were determined as 10.07 kWh/m(3) and 1.08 kg/m(3), respectively. (C) 2010 Elsevier B.V. All rights reserved.