Laboratory scale tests were developed to study the high consumption of water in a tannery in Toluca City, Mexico, needed to decrease the biological oxygen demand (BOD) in the wastewater. Biological oxygen demand is generally reduced by reducing the organic material with sodium hypochlorite. However, Cr(VI) is formed in this last process. Hydrotalcite (HT) and its calcination product were applied to separate the Cr(VI) formed. The best material found was calcined hydrotalcite, which removed not only Cr(VI) from the wastewater but also other anions, such as Cl-, SO42-, and HCO3-.