Calcium carbonate. It's alkaline, so it needs acid to shift it. Use vinegar to get rid of it. Boil in the kettle, and it will loosen it. Just make sure you rinse well before you make your next cuppa.
Or buy a water filter and only use filtered water in your kettle etc.
Not really, and for the main part Swiss water is actually not very hard, when compared with areas of the UK and France in which I have lived (or still do). It's just such a normal thing across most of Europe that everyone has to deal wth it one way or another.
Although some Swedish friends of ours did say recently that in Sweden they'd never even come across the concept.
It's actually very good for your heart, you'll be pleased to know. Very hard water here in the Jura as it is limestone country- and very pure water too, as it is slowly filtered through the limestone.
I buy cheap clear alcohol vinegar in France, for about 30 cts a litre- and use it neat on a cloth on tiles, taps, and all surfaces. As said above too, I pour some in the kettle about once a week and leave it to dissolve the limescale (kalk/calcaire) overnight then rinse thoroughly before using.
Is it really good for your heart? I always thought too much calcium was bad for the heart (and that's why some people have to take calcium channel blockers or something like that?). I have no idea, but I'm curious because I do have a heart condition, thanks to a C-section.
When we investigated a water softening system, we were advised to keep a drinking water tap off the system, as it is better for the heart, osteoperosis, etc. and because the increased sodium content (salt) can be dangerous for health.
I'm too scared to boil tap water for my baby girl's milk due to the calc, and thus use Aldi's bottled water 6 litres for 1.20 chf. Probably better value and less effort than using britta filters.
I thought that the mineral (and salt) content of bottled water can be higher than tap water. Not to mention the storage of water for a long time in plastic - that can't be good for us.