The Bluelab Guardian is a constant indicator of the desired levels of EC, pH and temperature, enabling the grower to optimize these parameters as the crop progresses through each growing phase. A flashing display lets gardeners know if one parameter moves away from the desired level, allowing them to make the required adjustments quickly. The Guardian monitors crops 24 hours a day with a built in alarm system, and also features large, easy to read displays with adjustable 'Plant Safe' green LED lights, adjustable conductivity and temperature values, push-button pH calibration, a silent alarm for both high and low settings, setting retention even during power failure, automatic temperature compensation, and a water resistant design. The meter ranges are: pH from 0.0 to 14.0 with a 0.1 resolution, EC from 0.00 to 5.00 with 0.1 resolution, and temperature from 0 to 50 degrees Celsius (32-122 degrees Fahrenheit) with 1 degree resolution. The accuracy is ±0.1 for pH and EC, ±1 Celsius (±2 Fahrenheit) for temperature. Protected by two-year manufacturer's warranty.