Calcium quantity in water?

Hi,

I'm in Spain where the tap water is very chlorinated and has lots of
calcium in it (and probably lots of other, less noticeable things), so
for tea making bottled water is used.

I'm wondering what to look out for in bottled water, all the bottles
here have to have a breakdown of calcium, chlorine, sodium etc on their
label so it is easy to tell what's in them.

Is calcium quantity one of the main things to look for (I think I read
this somewhere, but never had it confirmed)?

Two of the big makers of water here have dramatically different calcium
levels in their water, one being 5mg/l, the other being more like
35mg/l. The much cheaper bottles have higher amounts still. What is a
good amount to have? Can there be too little?

Any help, or other tips about what to look for in bottled water to make
a good brew would be much appreciated.

Quite apart from what it does to tea, calcium is a necessary nutrient.
Check out that you have enough other sources of it if you take it out
of your water, Toci

Thanks for the replies.

Iron isn't listed on the label so unfortunately I can't check that,
but I'll look into the PH of the different bottles, and at filters.

One of the bottles does leave a film on the cup and sometimes a layer
along the top after brewing. I presume this is the 'somewhat basic'
water described by Eric J.

I'm getting an OK tasting tea, but nothing like as good (in my
opinion) as the tea made by the Glasgow water I'm used to, despite
being city water its some of the best tasting and best tea making water
I've come across.

WATER - 99% of tea is water, Tap water should be avoided since its
chemical treatment imparts undesirable flavors and odors which
interfere with the delicate aromatics of tea. (Home filters and other
water purification systems can minimize and, in some cases, eliminate
these problems.) The best water for tea brewing is spring water with a
natural mineral content that's neither too hard nor too soft. Since
T.D.S., "total dissolved solids," or mineral content measured in
parts per million varies greatly from water to water, you may want to
do your own taste-test of waters available in your area to determine
which one has the best flavor, body and compatibility with the tea you
drink. An interesting Distilled water is not recommended for tea since
water purified of its mineral content produces a flat-tasting infusion.
icetea