Waterdrop X8-PRO Reverse Osmosis System: features, specs and who it suits

The Waterdrop X8-PRO is a tankless reverse osmosis (RO) system that fits under a kitchen sink. Its distinguishing feature is a dual-flow design, with one line for drinking water at its own faucet and another that can feed other outlets. This page explains the specs and what to confirm before installing a system like it.

How reverse osmosis works

Reverse osmosis pushes water through a very fine semi-permeable membrane that lets water molecules pass while holding back most dissolved substances. Carbon and sediment stages usually sit before and after the membrane to handle chlorine, taste and particles. The result is typically water with much lower dissolved solids than the supply, with a stream of wastewater sent to the drain.

Nine stages and a 0.0001 micron membrane

Waterdrop lists 9 stages of filtration, built around an RO membrane rated at 0.0001 μm. The brand says it has been SGS-tested to reduce TDS, PFOA, PFOS, chlorine, fluoride, arsenic, lead and other impurities. Test results apply to the conditions in the test, so your own supply and pressure will affect real performance. If water quality is a concern, a lab test of your tap water helps you choose the right system.

Tankless and 800 GPD

Traditional RO systems hold water in a pressurised tank. The X8-PRO is tankless, so it produces water on demand, and Waterdrop rates it at 800 gallons per day (GPD). That figure describes the membrane's production capacity, not how many gallons you will use. The practical benefit is no wait for a tank to refill and more cabinet space, since the unit measures about 18.2 x 6.3 x 16.7 inches (46 x 16 x 42 cm) and weighs 36.5 lb (16.6 kg).

Dual water flow

One line goes to the supplied RO faucet for drinking water. The second line connects to your regular faucet for filtered water that is suited to cleaning. Waterdrop says it can also be connected to a dishwasher, refrigerator or ice maker. Check the manual for the fittings and any additional parts these connections need.

Digital faucet and water use

The included smart faucet displays TDS levels and filter life, so you can see when it is time for a change. Waterdrop lists a 2:1 pure-to-drain ratio, meaning one part of wastewater for every two parts of purified water. The RO filters are listed as lasting 24 months, and the brand describes the materials as BPA-free.

Installation notes

Waterdrop notes that fitting the faucet requires drilling a hole in the countertop, unless your sink already has a spare hole. Stone and solid-surface counters often call for a professional with the right drill bits. Under-sink systems also need a cold water supply, a drain connection and a power source for the booster pump, so follow the manual and local plumbing codes.

Who it suits

It suits households that want RO water at the sink and also want to feed an ice maker or refrigerator, and that have the cabinet space and a suitable water supply.

What to check before you buy

• Cabinet space: measure the unit's width, depth and height, including pipe access.
• Countertop: confirm whether you can drill a faucet hole or already have one.
• Power: the system needs an outlet under the sink.
• Water source: check the pressure and whether the supply is municipal or a well.
• Drain: plan how the wastewater line will connect.
• Upkeep: note the filter change schedule and replacement parts.

The short version

• Tankless dual-flow under-sink RO system rated at 800 GPD.
• 9-stage filtration with a 0.0001 μm RO membrane; SGS-tested by the brand's account.
• Digital faucet displays TDS and filter life.
• 2:1 pure-to-drain ratio and 24-month RO filters.
• Countertop drilling is needed for the faucet.

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