The HYDRA Nitrate Analyzer System from Electro-Chemical Devices offers a precision nitrate ISE electrode sensor and an integral self-cleaning sprayer. It monitors the concentration of dissolved nitrate as nitrogen in the water. The nitrogen measurement helps to optimize the methane being transferred to the digester, and as a result helps to reduce operating costs. Additionally, it provides a trend indication of the total nitrogen in the effluent. 800/729-1333; www.ecdi.com.