The Sludge Gun hand-held biosolids blanket level detector from Markland Specialty Engineering measures silt or biosolids interface levels in clarifiers, tanks and lagoons and helps provide biosolids level profiles. It lets users eliminate unnecessary pumping/dredging and monitor bed depth for regulatory compliance and prevention of carryover. The unit uses high-intensity infrared light to locate the biosolids blanket and overlying cloudy layer, in concentrations ranging from light flocs to thick blankets. Compact and weatherproof, it is suited for use on boats and catwalks. No calibration is required. 855/873-7791; www.sludgecontrols.com.