The developed tool, known as "LoDif BioControl", consists of a computer application that incorporates the control algorithms developed by the research group CalAgua during the last few years. These control algorithms, based on fuzzy logic, allow for an efficient control of both the aeration system and the biological nutrient elimination process in Wastewater Treatment Plants (WWTP), optimising the activated sludge process, as they achieve to keep nitrogen below the discharge limits with minimum energy consumption. The uniqueness of this tool consists of the incorporation of nutrient control algorithms based on low cost probes: oxygen, ORP (redox potential) and pH (a system protected by the patent of invention with preliminary examination titled "Control system for the biological elimination of nitrogen of wastewater by using low cost probes ", Ref. ES 2 345 090 B2).