In article , Alwyn
Williams writes
OK Thanks. Is it true that allowing tap water to stand for a few days before
watering helps with the hardness.

I wouldn't have thought so. I stand tap water for a couple of days
before adding it to the fish tank, but that's to lower the level of
chlorine and other additives. I don't think affects the hardness.
--
Kay Easton

Edward's earthworm page:
http://www.scarboro.demon.co.uk/garden/