Waterdrop G3P800
#6 in TanklessFull review
For a busy kitchen that wants fast RO water and low waste from a certified system, and can pay for it.
Amazon $849$849
3.3/5
For a household that wants fast, certified tankless RO for less than most rivals. Buyers without a spare faucet should get the brushed nickel version.
- 800 gallons a dayOutput
- $290 a yearFilters
- YesNSF/ANSI 58
Check price at Amazon$449.99Check price at Amazon$484.99
Price checked November 2, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Certified to NSF/ANSI 58 by IAPMO
- Less than one gallon goes down the drain per gallon made
- 800 gallons a day fills a glass in seconds
- Shuts itself off when it detects a leak
Cons
- Filters cost about $290 a year
- Needs an outlet under the sink
- The cheapest version comes without a faucet
How it scores
The rating comes from 6 measured or published factors, each scored 0-100 against fixed reference points for its type. How we rank explains each one.
Specifications
| Model number | AOS-DFRO800 |
|---|---|
| Filtration | |
| Output | 800 gallons a day |
| Stages | 2 |
| Remineralization | No |
| NSF/ANSI 58 | Yes |
| Other certifications | NSF/ANSI 372 |
| Replacement filters | $290 a year |
| Build | |
| Tank | Tankless |
| Smart faucet | No |
| Warranty | 2 years |
Alternatives in this type
Waterdrop G2P600
#7 in TanklessFull review
For a buyer who wants tankless RO at a low price and low running cost and can do without third-party performance certification.
Amazon $299$299
Aquasana HealthShield RO
#9 in TanklessFull review
For a buyer who wants the broadest certification in a fast tankless system and doesn’t mind the price. Most households get similar output for much less elsewhere.
Amazon $1,299.99$1,299.99
Compare
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