Waterdrop G5P700A review
Waterdrop G5P700A Alkaline Mineral pH+ Reverse Osmosis Water Filter, 700GPD
By Tom Calder
A capable tankless RO system: the 2:1 pure-to-drain ratio wastes far less water than older RO designs, and the post-filter mineral stage puts back the calcium and magnesium that plain RO strips out, so it doesn't taste flat. It's a considered, plumbed-in purchase rather than an impulse buy — budget for annual filter changes on top of the unit price. One caveat worth weighing: it's mains-powered with no storage tank, so a power cut means no filtered water at all — pair it with a gravity-fed or manual filter if outage resilience matters to you.
- Best for
- Hard-water households who want compact, tankless under-sink filtration and don't mind the plumbed install.
- Skip it if
- You just want fresher-tasting tap water without a plumbing job
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.We earn a commission if you buy through the retailer links on this page. It doesn't change our verdict. How we make money →
Researched, not used. We haven't used this product. This review is built from the maker's specifications, owner reports and our own sizing.
What we like
- 2:1 pure-to-drain ratio is genuinely efficient — far less wasted water than typical RO systems
- Tankless design saves cupboard space and avoids the stale-water taste of stored-tank RO
- 8-stage filtration with alkaline remineralisation gives better-tasting, less flat water than plain RO
Worth knowing
- Waterdrop doesn't state WRAS approval for this model — get a plumber to confirm suitable backflow protection under the Water Supply (Water Fittings) Regulations before installing
- Ongoing cost: pre-filters every ~6 months and the RO membrane every ~2 years, roughly £60–£80/year on top of the unit price
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Our review
The alkaline member of Waterdrop's tankless reverse-osmosis range: eight stages, up to 700 US gallons (about 2,650 litres) a day, a 2:1 pure-to-drain ratio, and a final cartridge that returns calcium, magnesium, sodium and potassium to water the membrane has stripped bare. That mineral stage is what matters most: it is the difference between RO water that tastes flat and water most people drink happily. For hard-water households that want RO without RO's taste.
What it is
Waterdrop rates the G5P700A at 700 gallons a day, which it illustrates as a 177 ml cup in about six seconds, from a cabinet 42.4 cm wide, 14.5 cm deep and 35.3 cm high weighing 9.7 kg on Waterdrop's UK specification, the smallest and lightest of the three Waterdrop RO units we review. There is no storage tank; a pump makes water as the tap opens. The tap has a display for live TDS and filter life.
Certification is by IAPMO R&T to NSF/ANSI 58 (the reverse-osmosis performance standard) for the claims on its performance data sheet, and to NSF/ANSI 372 for low-lead materials; Waterdrop also says SGS tested it for PFOA and PFOS reduction. The listed reductions include TDS, PFOA and PFOS, chlorine, fluoride, barium, chromium-VI, lead and microplastics. Note what is not on the list: unlike the G3P600, it does not carry the NSF/ANSI 42 and 53 marks.
The mineral stage, and what the TDS display will show
After the membrane, water passes through a cartridge that Waterdrop says adds calcium, magnesium, sodium and potassium ions. It publishes no pH figure or mineral concentration, so treat 'alkaline' as a taste claim rather than a health one. One practical consequence: the tap's TDS reading will sit higher than on a plain RO unit, because the minerals it adds count as dissolved solids. That is the stage working, not the membrane failing.
In a British kitchen
You need a cold-feed tee, a drain saddle for the waste water and a socket for the power adapter; everything except the socket is in the box, and Waterdrop says it is designed for DIY in minutes with no special tools. WRAS approval is not stated, so the Water Fittings Regulations' requirement for backflow protection falls to you or your plumber; a WaterSafe-registered installer is the safe choice.
One gap in Waterdrop's listings: it does not state a feed-pressure range for this model, where it gives 14.5 to 87 psi (1 to 6 bar) for the G3P600 and G2P600. If your pressure is unusually low, ask Waterdrop before ordering rather than assuming. Hard water is where RO earns its keep: Waterdrop says RO filtration reduces limescale, and the mineral stage then puts a little back for taste.
When the power goes off
Tankless and pump-driven means nothing comes out of the filtered tap in a power cut. Your ordinary cold tap is unaffected, and UK mains water is safe to drink unfiltered, so plan around it with stored water rather than expecting the filter to help; see how to store emergency water.
How it compares
The G3P600 is the certification choice: slower at 600 gallons a day, heavier at 14.7 kg, no mineral stage, but tested to NSF/ANSI 42, 53 and 58. The G2P600 is the budget choice: seven stages, mechanical tap, no minerals, NSF 372 only. Waterdrop's own G5P500A sits just below this unit at 500 gallons a day with the same mineral stage; it is in our under-sink comparison but not reviewed separately. For a tank and UV instead, see the iSpring RCC7AK-UV, with its own pressure caveats.
Living with it
Two cartridges: the G5P700A-CF pre-filter every six months or 550 gallons (about 2,080 litres) and the G5P700-RO membrane every 24 months or 2,200 gallons (about 8,330 litres). Waterdrop's FAQ hedges that filters 'typically last between 6 to 12 months depending on usage and water quality', so take the display's word over the calendar. Warranty is one year for manufacturing defects, with 30-day returns and 30-day price protection from the UK store. It is for indoor use only.
Our verdict
Buy it if you are in a hard-water area, want reverse osmosis but have tried RO water and found it lifeless, and have a drain and socket under the sink. It is the one in the range most people will actually enjoy drinking from. Choose the G3P600 instead if the full NSF 42, 53 and 58 certificate set matters more than taste, and skip RO altogether if your water is soft and your only complaint is chlorine.
A researched review, built from the maker's specs, manual and UK listings; facts checked 21 Oct 2026. Sources: Waterdrop G5P700A product page (Waterdrop UK); Waterdrop G5P700A specifications (Waterdrop US).
Who shouldn't buy this
Skip this if you just want fresher-tasting tap water without a plumbing job — UK tap water is safe to drink, and a basic carbon jug or tap-mounted filter fixes taste, chlorine and scale complaints for a fraction of the price and hassle of a plumbed RO install.
Key specs
| Filter technology | 8-stage reverse osmosis plus a post-RO alkaline |
| Filter life | CF pre-filter ~6 months, RO membrane ~24 months |
| Flow rate | 700 GPD rated output |
| Installation | Tankless under-sink unit, DIY-fit |
This is a Researched review: we haven't used this product. We check every specification against at least two independent sources, re-check the UK price on a schedule where we can track it automatically, and say plainly who it isn't for. Commissions never change a rating.
If this isn’t the one
Best for Renters and homeowners who want better-tasting, chlorine-free tap water fast, without drilling a tap hole or fitting a drain line.
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.
Best for Hard-water households who want a compact, tankless under-sink RO system with alkaline remineralisation and have a spot with mains power and a drain nearby.
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.
Best for Households who want one permanent, fully-specced under-sink system — tap, install kit and all three cartridges in one box — rather than piecing parts together.
as of 5 Nov 2026, 22:07 GMT · Details
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.co.uk at the time of purchase will apply to the purchase of this product.Questions
Does the Waterdrop G5P700A need a drain?
Yes. Reverse osmosis produces waste water, one litre for every two kept at Waterdrop's 2:1 rating, and it leaves through a drain saddle clamped to the sink waste pipe. The saddle, tubing and clips are in the box.
Does the Waterdrop G5P700A work in a power cut?
No. It has no storage tank and the pump needs mains electricity, so the filtered tap gives nothing until power returns. Your normal cold tap is unaffected.
How often do the Waterdrop G5P700A filters need changing?
Waterdrop rates the CF pre-filter at six months or 550 gallons and the RO membrane at 24 months or 2,200 gallons; the tap display counts down each one. Heavy use or very hard water shortens both.
Is the Waterdrop G5P700A WRAS approved?
Waterdrop does not state WRAS approval. It is certified by IAPMO R&T to NSF/ANSI 58 and 372, which are American standards. Under UK rules a plumbed-in filter still needs an isolation valve and backflow protection, so use a WaterSafe-registered plumber or check the fittings yourself.
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