On 21 Sep, 15:48, "Why?" wrote:

My daughter has just moved into a flat at Brighton. *

Lay your own pipeline and get water piped in from somewhere civilised.
Brighton's tap water is disgusting.

She has cited a UK Water filterhttp://www.uk-water-filters.co.uk/water_filters_reverse_osmosis.html?...

Which seems to me merely to filter (reverse osmosis plus filters)
drinking and cooking water at a slow rate and store it under sink for
later reuse

If I lived in Brighton I'd have a Brita or two in the fridge (and a
bigger fridge) for starters. RO water isn't the most pleasant stuff
to drink either.