![Amazon.com: Bluelab MONGUA Guardian Monitor for pH, Temperature, and Conductivity (TDS) Measurements in Water with Easy Calibration, 3 in 1 Digital Nutrient Meter for Hydroponic System and Indoor Plant Grow White : Amazon.com: Bluelab MONGUA Guardian Monitor for pH, Temperature, and Conductivity (TDS) Measurements in Water with Easy Calibration, 3 in 1 Digital Nutrient Meter for Hydroponic System and Indoor Plant Grow White :](https://m.media-amazon.com/images/I/7115ij4unbL.jpg)
Amazon.com: Bluelab MONGUA Guardian Monitor for pH, Temperature, and Conductivity (TDS) Measurements in Water with Easy Calibration, 3 in 1 Digital Nutrient Meter for Hydroponic System and Indoor Plant Grow White :
![Amazon.com: Bluelab MONGUA Guardian Monitor for pH, Temperature, and Conductivity (TDS) Measurements in Water with Easy Calibration, 3 in 1 Digital Nutrient Meter for Hydroponic System and Indoor Plant Grow White : Amazon.com: Bluelab MONGUA Guardian Monitor for pH, Temperature, and Conductivity (TDS) Measurements in Water with Easy Calibration, 3 in 1 Digital Nutrient Meter for Hydroponic System and Indoor Plant Grow White :](https://m.media-amazon.com/images/I/71S4ykv40lL.jpg)
Amazon.com: Bluelab MONGUA Guardian Monitor for pH, Temperature, and Conductivity (TDS) Measurements in Water with Easy Calibration, 3 in 1 Digital Nutrient Meter for Hydroponic System and Indoor Plant Grow White :
![Amazon.com: Bluelab MONGUACON Guardian Monitor Connect for pH, Temperature, and TDS in Water with Data Logging (Connect Stick not Included), Nutrient Meter for Hydroponic System and Indoor Plant Grow White : Industrial Amazon.com: Bluelab MONGUACON Guardian Monitor Connect for pH, Temperature, and TDS in Water with Data Logging (Connect Stick not Included), Nutrient Meter for Hydroponic System and Indoor Plant Grow White : Industrial](https://m.media-amazon.com/images/I/710SJHct2fL._AC_UF894,1000_QL80_.jpg)
Amazon.com: Bluelab MONGUACON Guardian Monitor Connect for pH, Temperature, and TDS in Water with Data Logging (Connect Stick not Included), Nutrient Meter for Hydroponic System and Indoor Plant Grow White : Industrial
![Bluelab Guardian Monitor - 2 year warranty (6 months on probe). – Sunset Hydroponics and Home Brewing Bluelab Guardian Monitor - 2 year warranty (6 months on probe). – Sunset Hydroponics and Home Brewing](https://www.sunsethydro.com/cdn/shop/products/256214414113-2.jpg?v=1495821666)