Review on 🌡️ Bluelab MONGUA Guardian Monitor: pH, Temperature, and Conductivity (TDS) Measurement for Water | Easy Calibration | 3-in-1 Digital Nutrient Meter for Hydroponic Systems & Indoor Plant Growth (White) by Zack Frazier

This is the biggest piece of junk I have ever bought, I bought a new unit on 02/16/2018, it took 8 days and the PH - Sensor works perfectly. I called and ordered another one, received a new one and the PPM wasn't immediately readable. wahhh So, I bought the 3rd device. This lasted 10 days and PPM stopped working on this one. So I ordered my 4th and last one today on March 26th, 2018. 40 days later I'm now on my 4th monitor. This thing has some serious issues, I would never trust the readings, you'd better have some handheld devices to back up the readings. That fake monitor just ruined everything.