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Waterdrop G2P600 tankless RO system: features, specs and who it suits
A tankless under-sink reverse osmosis system with 600 GPD output, a 2:1 drain ratio and tool-free filter changes. What its specs mean for your kitchen.
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The Waterdrop G2P600 is a reverse osmosis (RO) system that sits in the cabinet under the kitchen sink. It has no storage tank, produces up to 600 gallons of filtered water a day, and sends one cup to the drain for every two cups it filters. Here is what those numbers mean, and what to check under your sink first.
How reverse osmosis works
An RO system pushes water through a membrane with extremely fine pores. Water passes through, while most dissolved solids are held back and flushed away down the drain, which is why every RO system produces some wastewater. RO systems are commonly used to lower total dissolved solids (TDS). Pre-filters in front of the membrane protect it from sediment and chlorine.
Waterdrop lists seven stages of filtration in the G2P600, packed into two filters: a CF filter and an MRO (reverse osmosis) filter.
What 600 GPD and a 2:1 drain ratio mean
GPD means gallons per day. 600 GPD works out to about 25 gallons (95 litres) an hour if the system ran nonstop. That matters for a tankless system, because there's no tank of water waiting: it filters as you pour. Waterdrop says it fills a 200 ml cup in 8 seconds. Real output depends on your water pressure and temperature, since RO membranes typically slow down in cold water.
The drain ratio compares filtered water to wastewater. At 2:1, you get two cups of filtered water for every cup that goes down the drain. Older RO designs commonly send several cups to the drain for each cup they filter.
Why tankless matters under the sink
Traditional RO systems hold filtered water in a pressurised tank that takes up a large part of the cabinet. The G2P600 is a single unit of about 17.3 x 5.9 x 14 inches (44 x 15 x 36 cm). Waterdrop's diagram suggests leaving about 4 inches (10 cm) above it.
Tankless RO systems generally use a built-in pump to push water through the membrane, so the G2P600 needs an electrical outlet under the sink. Waterdrop says you can install it yourself in about 30 minutes.
Filters and upkeep
Two filters come in the box. They twist and pull out, so Waterdrop says a change takes about 3 seconds, with no tools and no need to move the unit. Filter life indicators remind you before a change is due.
Waterdrop lists up to 12 months for the CF filter and up to 24 months for the MRO filter. Actual filter life depends on your water quality and how much water you use, so follow the indicators rather than the calendar. Replacement filters are specific to the G2P600.
What NSF/ANSI 372 certification means
The G2P600 is certified to NSF/ANSI 372 for lead-free materials. This standard covers the lead content of the materials in products that come into contact with drinking water, so it is about the system's own components. It is not a test of what the system removes from water.
Who it suits
Waterdrop describes it for drinking water and for washing fruit and vegetables, and says its output meets the needs of big families and offices. It suits households that use a lot of filtered water every day and want the cabinet space a tank would take.
What to check before you buy
- Cabinet space: measure the area under your sink against 17.3 x 5.9 x 14 inches, plus room above for filter changes.
- Power: you need an electrical outlet under the sink.
- Faucet: RO systems usually dispense through their own faucet; check whether your sink or countertop has a spare hole, and what's in the box.
- Water supply: check the manual's requirements for water pressure, temperature and source, especially on well water.
- Filters: plan for replacement CF and MRO filters over time.
The short version
- A tankless under-sink reverse osmosis system with seven stages of filtration in two filters.
- Up to 600 gallons per day, with a 2:1 ratio of filtered water to wastewater.
- Twist-and-pull filters with life indicators; Waterdrop lists up to 12 months (CF) and 24 months (MRO).
- Certified to NSF/ANSI 372 for lead-free materials.
- About 17.3 x 5.9 x 14 inches, needs an outlet, and Waterdrop says it installs in about 30 minutes.
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