A maximum /minimum memory tells you what is happening when you are not there; at night, or during the day. Learn how your plants are going by looking first at the plants then looking at this meter. The plants will be telling you if things aren't perfect. The meter will confirm if it is temperature and/or humidity or not. Then reset it for tomorrow.
 
Use the probe to measure the root zone, or the intake temperature, or the water temperature. Get creative.
 
This tool is a very important addition to your hydroponic grow greenhouse or grow room tent.
 
Temperature and Humidity meter with a maximum and minimum memory and a temperature probe for reading root zone or air or water temperatures.