This guide was written by Keith, a mechanical engineer with over 20 years of hands-on experience working with reverse osmosis and water filtration systems.
A no-jargon explanation by FilterAuthority.co.uk
No chemistry degree required.
There are dozens of water filters on the market — but only a handful of filter types.
This guide explains each one in plain English, what it actually does, and who it's suitable for.
Remove visible particles like sand, grit and rust.
No.
Absorb contaminants onto carbon.
Under-sink
Countertop
Whole-house
Best all-rounder for UK homes.
For drinking water, carbon block is usually better.
Pushes water through a membrane that blocks contaminants.
Under-sink
Drinking tap only
Use ultraviolet light to neutralise bacteria and viruses.
Best used after sediment + carbon.
Replace calcium/magnesium with sodium.
Often paired with a drinking-water filter.
Treat all incoming water.
Often combined with under-sink RO for drinking.
Basic taste improvement.
Convenient — but limited.
That depends on:
That's why FilterAuthority provides:
(personalised guidance)
Different tools for different jobs — RO is stronger, carbon is simpler.
Often yes — staged filtration works best.
No — beware of exaggerated claims.