The DOH-SD1 series dissolved-oxygen meter is said to be easy to operate. It integrates a real-time SD card data logger, setting it apart from comparable meters. CE-qualified, it features a LCD with green light backlighting, altitude and salt adjustments, RS-232/USB interfaces with optional cable, and automatic temperature compensation. Price starts $700. OMEGA ENGINEERING INC., Stamford, CT. (800) 872-9436.