COMMENT:

No. Gallstones have very little to do with mineral balance. Kidney
stones are of various types, but the bottom line is they are not
increased in frequency by calcium or magnesium supplementation (which
is surprising but true), and so certainly should not be affected by the
very little bit of extra calcium and magnesium you get from hard water.

You should drink all the water (or juice) you can. Urine calcium is
influenced by vitamin D intake/production, so limiting milk and using a
sunscreen might be a good idea. Useful supplements include B6 (no more
than 100 mg a day) and (assuming you don't have stones as a result of
chronic urinary infections) magnesium citrate (as much as you can take
without getting over-loose stools). Depending on the kind of stone,
there are also some prescription drugs which can help. If you pass one,
keep it because you'll want it analyzed. (See your doc-- you may have
to urinate though a fine mesh strainer for a while to get one).

SBH