dfk41 Jony I found a system which seems to produce good RO water on special offer @£289. It is so far so good. I have to add a bit of bicarb to the water I put into the Evo but it is a simple enough thing to do! https://www.waterdropfilter.co.uk/collections/portable-reverse-osmosis/products/instant-hot-water-reverse-osmosis-system-wd-k19-h