In such a study, Marquez and Costa [1] obtained 90% acid orange 7 dye removal efficiency by addition of activated carbon into the aeration tank. It was also determined that the increase in activated carbon particle size decreases color removal efficiency [1]. In another study, the addition of activated carbon was investigated and color removal efficiencies for different kinds of dyes were determined [2]. While color removal efficiency was over 90% for mordant, cationic, and acidic dyes, it was more than 40% for direct, sulfur and dispersed dyes, over 50% for reactive dyes and under 20% for vat dyes. Although in wastewater treatment, generally, activated carbon is used as the adsorbent (either in powdered or granulated form), other materials including bentonite, barbecue charcoal, vermiculate, sawdust, dried crushed maize stalks, sand peat moss and dried ground rice hulls have also been examined for color removal. The most effective one was found to be the barbecue charcoal resulting in a color removal efficiency of 67% [3].