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Under sink reverse osmosis

Waterdrop G3P800

G3P800 Black Faucet / WD-G3P800-Black

$999US price, checked Oct 13, 2026

Fast tankless RO with a 3:1 drain ratio and unconfirmed certification

Check price at Waterdrop Full review →

Under sink reverse osmosis

APEC ROES-50

ROES-50 Essence 5-stage, 50 GPD

$230.99US price, checked Oct 13, 2026

Cheap tank RO with low filter costs and output that depends on your water pressure

Check price at APEC Full review →

Criterion	Waterdrop G3P800	APEC ROES-50
US price	$999Checked Oct 13, 2026 · Price details in the review	$230.99Checked Oct 13, 2026 · Price details in the review
Three-year ownership estimate	$1,478.91 Incomplete known subtotal. Not included: installation, energy use.	$395.90 Incomplete known subtotal. Not included: installation.
Choose if	A household on city water that wants quick RO flow and less drain water than a 2:1 system.	You want RO water at one kitchen sink for little money, and your water pressure is near 60 psi.
Main trade-off	NSF doesn't list it, Waterdrop doesn't publish the power draw, and the warranty is one year.	Output falls to 30 GPD at 50 psi, and APEC's contaminant claims aren't backed by a confirmed certifier listing.
Key specifications	Rated output: 800 GPD; Waterdrop says it fills a 6 oz cup in 5 seconds Pure-to-drain ratio: 3:1 Filter life: G3-N1CF 6 months or 550 gal, G3-N3CB 12 months or 1,100 gal, G3P800-N2RO membrane 24 months or 2,200 gal Certification claim: NSF/ANSI 42, 58 and 372 in the feature list, plus 53 in the spec table. No certifier named in the page text, and no NSF listing found Power: Needs an outlet (adapter included); wattage not published Faucet: Smart display with TDS and filter-life readout Size and weight: 18.11 × 5.67 × 17.73 in (axes not labeled), 32.4 lb	Rated output: 50 GPD at 60 psi and 77°F (about 1.8 gal an hour); 30 GPD at 50 psi Drain water: Not published for the ROES-50; APEC's FAQ gives about 3:1 for under-sink systems in general Tank: 4 gal total volume (bladder and air space); about 3.2 gal bladder capacity at 80 to 90 psi; refills in 1.7 to 3 hours (FAQ) or 2 to 3 hours (manual) Filter life: Pre-filters every 6 to 12 months; membrane and stage 5 every 2 to 4 years (the manual says 2 to 3) Feed water limits: 40 to 85 psi; 40 to 100°F; up to 2,000 ppm TDS; pH 2 to 11 Certification: APEC claims WQA certification for TDS reduction; no NSF listing; WQA listing not confirmed Power: None; the manual describes a non-pumped system
Exact variant	G3P800 Black Faucet / WD-G3P800-Black	ROES-50 Essence 5-stage, 50 GPD
Dimensions	18.11 × 5.67 × 17.73 in and 32.4 lb, per Waterdrop's product page. Waterdrop doesn't say which measurement is width, depth or height, or how much clearance you need to swap filters.	System 15.5 in L × 5.25 in W × 17 in H. Tank 11 × 11 × 15 in. Package weight 26 lb. The manual says to allow about 17 × 6 × 18 in for the system and 11 in across and 18 in tall for the tank.
Installation	It goes under the sink and connects to a water supply line, a drain and its own faucet. The box includes the faucet, a 3/8 to 1/2 in feed-water adapter, a 1/4 in drain saddle, tubing, lock clips and Teflon tape. It also needs an outlet, and a power adapter comes in the box. Waterdrop calls it a 30-minute DIY install that needs no plumbing skills. It's for indoor use only. The product page doesn't give the faucet-hole size or any water limits, and the linked user manual PDF has no searchable text. The only limits Waterdrop publishes are general ones in its extended-warranty terms, not specific to the G3P800. They call for municipal tap water at 14.5 to 87 psi and 41 to 100°F. TDS should be under 750 ppm and hardness under 7 grains per gallon. Well water needs pre-filtration.	APEC sells it as a do-it-yourself install and links a general RO installation video. It connects to the cold-water line only, using the included 1/2 in feed adapter and valve. You drill a 1/2 in hole for the standard faucet (1-1/4 in for an air-gap faucet) and a 1/4 in hole in the drain pipe for the drain saddle. Tubing is color-coded with quick-connect fittings. Feed water must be 40 to 85 psi, 40 to 100°F, under 2,000 ppm TDS and pH 2 to 11. The warranty doesn't cover damage from installation.
Materials	A tankless unit that Waterdrop calls 10-stage, built around three replaceable filters: the G3-N1CF, the G3P800-N2RO reverse osmosis membrane and the G3-N3CB. The membrane page describes this as a 3-filter setup with a seven-layer RO membrane. Waterdrop says the membrane is 0.0001 μm, though the membrane page's FAQ says 0.001 microns. The box list includes a UV sterilizer, and the faucet's display shows TDS and filter life. Waterdrop's comparison table marks alkaline mineralization as not included. Housing, tubing and faucet materials aren't listed.	Five stages: a 5-micron polypropylene sediment filter, two 10-micron carbon block filters, a high-rejection TFC RO membrane and a 10 in coconut-shell refining carbon filter for taste. The kit includes a lead-free faucet, food-grade tubing, a stainless steel check valve and a flow restrictor. APEC doesn't state the tank's material.
Warranty	One year against manufacturing defects, per the product page. Waterdrop's service policy says most of its RO systems carry a one-year limited warranty and that terms vary by model. If it fails from a quality problem during the warranty, Waterdrop will take it back, repair it or replace it for free. The policy's extended-warranty terms apply only to purchases from Waterdrop's US website. They exclude filters and damage from well or river water. They also exclude damage from incorrect installation, use or maintenance, or from unauthorized repairs. The policy asks you to report a defect within 30 days of finding it. It doesn't say how the extended terms relate to the standard one-year warranty. Waterdrop also offers lifetime technical support for eligible models.	One year from the purchase date, covering defects in materials and workmanship. Used filter cartridges and membranes are excluded. It's void if you aren't the original purchaser, or if you run it outside normal municipal or well water conditions. The manual also voids it if you bought the unit used or from anyone other than APEC or an authorized dealer. Coverage depends on changing filters as the manual directs, and damage from non-APEC parts is excluded. A claim needs a return goods authorization number, and you pay to ship the unit to APEC. APEC's FAQ promises lifetime technical support.
Returns	30-day returns, counted from receipt, for orders within the continental US. Items must be disassembled and repacked as received, in the original packaging with the receipt. There's no restocking fee within 30 days, but you pay return shipping unless the return is for a quality problem. After 30 days, Waterdrop charges a 10% restocking fee and deducts shipping from the refund. An item that isn't like new also carries a 10% fee. If it arrives damaged or wrong, email service@waterdropfilter.com with your order details and a photo. Orders from Amazon and other third-party sellers aren't covered. The policy doesn't say whether an installed system counts as like new.	You can return it within 30 days of the invoice date with an RMA number, and it must reach APEC within 15 days of the RMA. You get a full refund, less shipping and handling, only if it's unused in unopened packaging. Opened but unused costs a 10% fee, missing parts or damage 15% to 45%, and used but not defective 50%. You pay return shipping unless the return is APEC's error or a defect. The policy covers only orders from apecwater.com.
Unresolved questions	Which body, if any, certifies the G3P800 to NSF/ANSI 42 or 58, and which contaminants a listing covers Who issued the NSF/ANSI/CAN 372 certificate shown in a product image, and what it covers Whether the NSF/ANSI 53 claim in the spec table holds, since the feature list leaves it out What SGS and CSA tested, to which standard, and the results behind the PFOA, PFOS and lead reduction claims What the WQA entry on the membrane's page refers to Power draw and how long the pump runs each day G3P800-specific pressure, temperature and feed-water TDS limits Faucet-hole size and clearance needed for filter changes Which of the three listed dimensions is the width What the $89.97 G3P800 replacement-filter combo linked from the membrane page contains Whether an installed system can be returned Real output and drain volume at your water pressure and temperature	The ROES-50's own pure-to-drain ratio Whether a WQA or IAPMO listing covers the ROES-50, and which contaminants it lists The membrane's TDS rejection rate How much water the tank delivers at typical home pressure, since the manual's 3.2 gallons is at 80 to 90 psi Test data behind the "Guaranteed to Remove" contaminant list Installed cost if you hire a plumber Price of O-rings, and whether the $14.95 Essence post-filter is the ROES-50's exact stage 5 part

These comparisons use published specifications, not head-to-head tests. Prices and terms are dated. Unknown costs are not zero. Check the exact variant before you buy.