Better crops start with the Bluelab Guardian Monitor, it’s all you need for simple and reliable crop management and it’s all within arms reach. It is a conductivity, pH and temperature meter all in one. It comes with a pH probe and conductivity/temperature probe, which are simply placed into the solution and the selected reading is displayed on screen. Simply set high and low alarm states, if the solution moves away from the ideal range, the display flashes. A quick look at the monitor will let you know when your nutrient solution needs adjusting.