The pH controller will track pH, which is directly related to CO2 concentration. The pH controller will keep pH and CO2 releases consistent and appropriate for your aquarium. Can be used for every purpose, from a goldfish bowl to a full-blown reef tank. It can also be used for fish hatcheries, wine production, swimming pools, floristics, analysis of fluids (pH value), ponds, and other various industrial applications. Features: Large LED display Digitally adjustable control range High input impedance Built in SLOPE and CAL Front LED lamp indicate when relay "ON". Choice of wall-mount or hung in Includes a BNC connection Easy to calibrate replaceable pH electrode Controller will handle up to 5 amps Uses the Protection Dead Band feature, the controller automatically turned-off or shut down to protect your unit from erroneous readings Specifications: Measuring range: 0.00~14.00PH Accuracy: ±(0.1%+2 digits) after calibration Resolution: 0.01PH Set Range: 3.50~10.50PH Relay Contact : 5A for AC 110V / 220V Power Requirement : AC 110V / 220V ±10% 50Hz Voltage: 110V / 220V Environment: Temperature is 0°C~50°C and Humidity is