I have a regular upright fridge made by Hoover. I would like to buy a
water filter that fits inside the door. I know jug water filters are
available that are narrow enough to slot into the shelf, but I would
rather have something that behaves more like a tap, with a reloadable
canister of water. I'm aiming for a poor-man's variant of the external
cold water dispensers you find on side-by-side American fridges.

Does such a product exists? Can I buy them in the UK?

Peter