Waterdrop G3P800 Tankless Reverse Osmosis System: specs and who it suits

The Waterdrop G3P800 is a tankless reverse osmosis (RO) system that sits under the kitchen sink and sends filtered water to a separate faucet. Waterdrop designed it for fast flow, so you get water on demand without waiting for a storage tank to refill.

What reverse osmosis does

In general, an RO system pushes tap water through a very fine membrane, which holds back dissolved solids and many other substances, along with prefilters that handle sediment and chlorine. The water that doesn't pass the membrane goes to the drain. That is why the drain ratio is an important number on RO systems.

800 GPD and the 3:1 ratio

GPD means gallons per day, and the G3P800 is rated at 800. Waterdrop says that is enough for a large family and that the system filters a cup of water in about five seconds. The brand also states a 3:1 pure-to-drain ratio, so it produces about one cup of wastewater for every three cups of filtered water. Many tank-style RO systems waste more than that.

Tankless design

With no storage tank, the system is said to save under-sink space, and Waterdrop says the water stays fresh because it is produced as you use it. The unit measures about 18.1 x 5.7 x 17.7 inches and weighs 35.8 lb, so measure your cabinet before you decide.

10-stage filtration

Waterdrop says an SGS laboratory tested the 10-stage system and that it reduces PFAS, fluoride, heavy metals such as lead and chromium, iron, and salts such as nitrate and chloride, as well as large particles. The brand also cites the membrane's technical manual for reduction of certain chemicals. These are the brand's claims, so read the performance data sheet for the specific substances and reduction levels.

Certifications

The listing names four standards:

• NSF/ANSI 58: certified by IAPMO R&T for reduction of total dissolved solids (TDS).
• NSF/ANSI 42 and 53: tested to reduce chlorine, taste and odour, and certain contaminants.
• NSF/ANSI 372: certified for lead-free materials.

Smart faucet

The faucet shows the TDS level so you can see water quality at a glance. An LED turns on automatically when water flows, and Waterdrop says the lamp lasts up to 50 years.

Who it suits

It suits households that want filtered drinking and cooking water from a dedicated faucet, with a smaller footprint than a tank system and a quick fill.

What to check before you buy

• Space: confirm the cabinet fits the unit and the plumbing connections.
• Water pressure: check the manual for the minimum supply pressure and whether a pump is needed.
• Drain and counter: check you can fit the faucet and drain saddle.
• Filter changes: look up how often filters and the membrane need replacing and what parts are available.
• Certificates: read the performance data sheets for what is tested for. Follow the manual and local plumbing codes.

The short version

• A tankless under-sink reverse osmosis system with 10 filtration stages.
• 800 GPD flow and a 3:1 pure-to-drain ratio.
• Certified to NSF/ANSI 42, 53, 58 and 372, as listed.
• Smart faucet with TDS display and an LED light.
• About 35.8 lb; measure the cabinet first.

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