Question about Krups Cleaning tablets

The Krups machine has a cleaning program that appears after X number of coffees. Even if the message that cleaning is required is displayed, it is still possible to make coffees. You have to put the tablet in the tank and then start the cleaning programme. Once the cleaning program is finished, you have to put water in the tank and "pass" the water through the machine to remove the cleaning residue.

There is a special programme for this. Then you open the metal cover on top of the coffee machine, put the tablet in and start the programme.