Pulsar's SludgeFinder sludge level monitor is an acoustic sensor that sits under the liquid surface of a clarifier or sludge tank. An acoustic signal is bounced off the bottom of the tank and modulations in the returning signal are interpreted to provide a profile of the sludge in the tank. Water companies can use this information to optimise chemical dosage and to save employees from having to make tedious and time consuming manual calculations. Unlike many other devices on the market, THIS ONE REALLY WORKS!