As the product instructions state, these tablets are ONLY "for removing coffee oil" and "will help you remove all coffee residues and oil...". They are NOT descaling tablets! That is, they do not remove the salts from the coffee machine. For use in automatic machines that have a portafilter, we place a tablet in this port (without adding coffee) and start the coffee preparation process. When the machine has dispensed about half the amount of water for making a coffee, we turn off the machine. Usually, we need to completely interrupt the power supply (unplug the machine from the socket). We let the tablet work for at least 20 minutes per hour and then we start the coffee machine again. The cycle is completed and we clean the machine thoroughly with clean water, rinsing both the internal mechanism and running water for coffee preparation (without coffee) 4-5 times. Inside the packaging of the tablets, there are instructions for both semi-automatic machines and automatic machines that do not have a portafilter. I use this product every month (I make about 250 coffees per month). However, my estimation is that even if someone makes fewer coffees per month, it is good to use it at least every two months, because the "coffee oil" gradually clogs the small holes from which extraction starts and it is quite difficult to remove them using the tablet. This results in the gradual alteration of the coffee taste. Finally, it should be noted that we should not expect spectacular results when using the tablet, as the unclogging process happens gradually and slowly, and the small differences are not easily noticeable. The use of the tablet maintains the quality of the coffee and does not clog the small extraction holes.