Waterdrop G5P500A Alkaline Reverse Osmosis System 500 GPD
- 500 GPD tankless reverse osmosis
- 8-stage filtration with alkaline remineralization
- 2:1 pure to drain ratio
- 0.0001 um RO membrane
- NSF/ANSI 58 & 372 certified
- 14.5-87 psi operating pressure, 41 to 100 F water
- Up to 500 ppm TDS supply water
- Faucet needs a countertop hole, drilling required
Last refreshed Sep 11, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A compact under-sink RO system that adds minerals back, for a kitchen short on cabinet space. It needs a power outlet under the sink and a hole for the faucet, and filter life is not stated.
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ASIN: B0DPH3198FModel: G5P500ACategory: Undersink & Countertop Water Filters
Overview
A kitchen sink cabinet short on room suits this tankless reverse osmosis unit, which filters on demand instead of storing water in a tank. A mineral stage adds calcium, magnesium and potassium back before water reaches its dedicated faucet.
Dropping the storage tank frees cabinet space and gives steady flow without waiting for a tank to refill. It plugs into power, needs a drilled faucet hole, and the listing leaves out how long each filter lasts.
Who it's for
Homeowners wanting purified drinking water with minerals restored get a tankless unit that also feeds an ice maker through an add-on kit. Renters barred from drilling counters will struggle with the faucet install.
Pros and cons
- Tankless design frees cabinet space
- Low waste water ratio
- Minerals added back after filtration
- Can feed ice makers with an add-on kit
- Countertop drilling needed for the faucet
- Needs electric power under the sink
- Filter life not listed
- Connector kit for appliances sold separately
Performance notes
Output depends on supply pressure and temperature: cold water or low pressure slows the membrane, while warmer feed water within the rated range raises flow. The electric pump drives water through the membrane, which is what lets a tankless unit fill a glass quickly.
Specifications
| Brand | Waterdrop |
|---|---|
| Model | G5P500A |
| Dimensions & fit | |
| Item Dimensions L X W X H | 16.69 x 5.69 x 13.9 inches |
| Item weight | 21.4 pounds |
| Faucet dimensions | 6.6 x 3.2 x 11.3 inches |
| Capacity & performance | |
| Capacity | 500 gallons per day |
| Maximum Flow Rate | 1.31 liters per minute |
| Operating Pressure Range | 14.5-87 psi |
| Lowertemperature Range | 41 F |
| Upper Temperature Rating | 100 F |
| Power & efficiency | |
| Power Source | Corded electric |
| Construction & materials | |
| Material Type | BPA-free |
| Compatibility & installation | |
| Installation Type | Under sink |
| Included components | |
| Included Components | G5P500A RO system with 2 pre-installed filters, mechanical faucet, user manual |
| Unit Count | 1 Count |
| Warranty & support | |
| Warranty Description | 1 year manufacturer |
| Supported Water Tds Level Maximum Ppm | 500 |
| Other details | |
| Purification Method | Reverse osmosis, 8 stages, alkaline mineral |
| External Testing Certification | NSF/ANSI 58 & 372 |
| Pure to drain ratio | 2:1 |
| Container Type | Dispenser |
Frequently asked questions
Is the Waterdrop G5P500A a countertop filter?
No. It installs under the sink and supplies a separate faucet that needs a hole drilled in the countertop.
Does the Waterdrop G5P500A need electricity?
Yes. The power source is listed as corded electric, so an outlet under the sink is needed.
What water pressure does it need?
An operating pressure of 14.5-87 psi, with water between 41 and 100 F and up to 500 ppm TDS.