The PET 2000 activity meter measures the dissolved nutrients available to the plant, thus indicating their "activity" in the root area. The measurement provides an overview of the nutritional status of the soil or substrate. The display is shown in g/l (i.e., grams of salt per liter of substrate). The evaluation of the measured salt concentrations is done using the accompanying technical manual. In horticulture, nurseries, landscape construction, public green spaces, forestry and agriculture, as well as in specialty crops, this device is used to ensure and verify already implemented or planned fertilization measures. The PET 2000 creates the best conditions for optimal cultivation success.