Ask HN: Tips for Cleaning a Rancilio Silvia

I know a few of you have a Rancilio Silvia coffee machine. Do you have any cleaning tips?

If you were making two shots a day, how often would you clean your Silvia?

Do you backflush the group head with Cafiza?

How do you clean the water tank, especially the hard to reach corner between the cross and the sides?

Do you ever descale the boiler?

Is Cafiza safe to use when cleaning the water tank separately (obviously rinsing it all out afterwards) or will it react with and degrade the plastic?

How often do you replace the silicone tubes?

Bonus: How do you clean your Rocky grinder?