My husband, the tablets on the advice has equal appointed with pillow. Finally, bacteria and germs in the water can form, and reproduce well. One tablet is intended for approximately 10 liters. So the pillow requires only half a tablet. The parts, however, is virtually impossible, because the tablets simply crumble and never can be divided exactly in the middle. Without further ado, we have always used for one year exactly a tablet. This stipulates that the remaining tablets are also, unfortunately, in this bag, are kept, which I personally find not so well resolved. Children can find, and they are, alas corrosive. Individual packages I have found better honestly.