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Honest Water Co
The Pure Alkaline filter stage fitted inline with a reverse osmosis system

Add Ons

Pure Alkaline Filter

Puts the good minerals back after RO takes everything out.

Reverse osmosis is thorough — it strips beneficial minerals along with the contaminants. The alkaline filter adds calcium and magnesium back in, which is what makes water taste like spring water instead of flat. Pairs with either RO system.

Best for: Anyone who finds plain RO water tastes flat

What you get

Features

  • Restores calcium and magnesium removed by RO
  • Noticeably better taste in water, coffee and tea
  • Installs inline with your existing RO system
  • Simple cartridge replacement

Full specifications

NSF-certified mediaPairs with any RO system

Key specifications

TypeInline remineralization cartridge
FunctionRestores calcium and magnesium removed by RO
InstallsInline, after the RO membrane
Pairs withHW800 AlkaPro (built in) or the 5-stage tank RO
Filter changesSimple cartridge replacement

Warranty

Media warranty5 years
Labor warranty1 year from date of purchase

What it adds back

  • Calcium
  • Magnesium
  • A noticeably fuller taste in water, coffee and tea
  • Balanced pH rather than flat, stripped water

Warranty on this system

Lifetime
Tanks, ceramic discs and dry parts
5 years
Control valve, circuit board and media
1 year
Installation labor
Full warranty terms and exclusions →

Specifications from the manufacturer’s documentation. Component brands and certifications are those of their respective manufacturers.

More photos

A closer look

Alkaline filter installed as part of a complete RO system
Alkaline filter installed as part of a complete RO system

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Reviews

From people who had one installed

System info and pricing

Find the right system for your water

Call or fill out the form, tell us what you're seeing at the tap, and we'll tell you which system fits your home and what it costs. There's no system that fits every house.

  • Complete installed price
  • Free installation
  • Lifetime warranty