Waterdrop G2P600 RO Water Filtration System, 600 GPD Tankless Filter review
Households wanting a compact, tankless under-sink RO system to sort taste, hardness scale and lead-pipe reassurance (pre-1970 homes) without a bulky reservoir.
By Tom Calder
A capable, keenly-priced entry point into tankless RO — noticeably improves taste and clarity, and the 2:1 pure-to-drain ratio is efficient by RO standards. It's a proper plumbed install rather than a jug swap: WRAS approval isn't stated for this unit, so fit it with the check-valve/backflow protection the Water Supply (Water Fittings) Regulations 1999 require for any plumbed-in device — ideally via a WaterSafe-registered plumber.
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- Tankless design saves roughly 70% of the cabinet space a tanked RO system needs
- NSF/ANSI 372 certified lead-free build, and an efficient 2:1 pure-to-drain ratio — roughly a third of the input water goes to drain, still better than most RO systems
- Simple filter-life tracking (time or gallon-based) and a mechanical faucet included in the box
- No remineralisation stage in this base model — RO strips out calcium and magnesium as well as contaminants, leaving water tasting flat and slightly acidic; a separate remineraliser is extra cost
- Needs a dedicated faucet hole and drain saddle, so installation is more involved than a countertop or jug filter
Who shouldn't buy this
you're renting, can't drill a faucet hole or access a kitchen drain, or you want mineral-restored water without buying a separate remineraliser stage.
Key specs
| Filter technology | 7-stage RO + carbon filtration |
| Filter life | Pre-filter ~12 months/1,100 gal |
| Flow rate | 600 GPD (~0.42 GPM), approx. 2,271 L/day |
| Installation | Tankless, under-sink |
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Alternatives to consider
as of 20 Sep 2026, 12:29 BST · 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.as of 20 Sep 2026, 12:29 BST · 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.Want this cheaper?
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