HW800 AlkaPro Tankless Reverse Osmosis
Tankless · 7-stage · alkaline
Seven stages of filtration, produced on demand, with no storage tank taking up the cupboard under your sink.
Water is purified as you draw it rather than sitting in a bladder tank waiting to be used. That gives you back most of the space a conventional system occupies — up to 70% of it — and with fewer fittings in the assembly, there is less that can ever leak.
It is also far less wasteful. A 2:1 drain ratio means two cups of purified water for every one sent to drain, where a conventional system sends considerably more away. The final stages put minerals back in, which is the difference between water that tastes clean and water that tastes like nothing at all.
Key features
- 0.0001 micron filtration. The membrane is rated by its manufacturer at 95–99% rejection across a wide spectrum of impurities including total dissolved solids, heavy metals, microplastics and PFAS “forever chemicals”.
- 2:1 low drain ratio — two cups purified for every cup to drain.
- Automatic RO flush. The system washes trapped impurities off the membrane itself, preventing clogging and extending membrane life.
- Lead-free water path built to NSF 372.
- DIY-friendly filter changes and a choice of faucet finishes and styles.
The filtration stages
- Stage 1 5-micron polypropylene sediment pre-filter to take out suspended material.
- Stages 2–3 Double NSF carbon block filters for chlorine by-products such as chloramine, THM and TCE, filtering organic matter without releasing carbon fines, and preparing the water before the membrane.
- Stage 4 NSF thin film composite RO membrane, 800 GPD — the stage doing the heavy lifting.
- Stage 5 In-line NSF coconut shell GAC filter to strip dissolved gases, taste and odour.
- Stage 6 Internal alkaline remineraliser — puts beneficial minerals back and balances pH.
- Stage 7 A second in-line NSF coconut shell GAC filter as a final polish.
Specifications
| Filtration stages | 7-stage high-precision |
|---|---|
| Filtration precision | 0.0001 micron |
| System capacity | 800 GPD |
| Water flow rate | 0.53 GPM |
| Drain ratio | 2:1 |
| Design | Tankless — saves up to 70% under-sink space |
| Alkaline remineralisation | Built in |
Certification
Tested and certified by NSF International against NSF/ANSI Standard 58 for TDS reduction, and against that standard's materials and structural integrity requirements. That certification covers TDS reduction specifically — the broader rejection figures above are the membrane manufacturer's performance ratings, not part of the NSF certification.
Backed by a lifetime warranty
Lifetime on system dry parts, 5 years on the control valve, circuit board and filtration media, and 1 year on installation labor. Full terms on the warranty page — written out in plain language so you can read them before you buy.
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