Shortly after I ordered you 900g bottle here. How do I find a very good value for money compared to the bags from retailers.
I take about a teaspoonful in the blind filter, about 10g, every 2 weeks. In addition, I have a soft the filter holder in warm water with about 5-10g Puly. Here you should make sure that the plastic handle is not resting with underwater. In the longer time seen, they told me at the store, the cleaner could attack the Kunsstoff. Thus, the bottle would hold about 2-3 years.
A normal side effect is a squeak of the lever to the brewing unit, but this disappears after 1-2 espressos, the fat it back of course. The 1st espresson after cleaning is with me anyway a "victim-Espresso".
On the homepage of ECM can be found, incidentally, a detailed guide to using such a cleaner - highly recommended.