1 / 7iSpring RO500-BN Tankless Reverse Osmosis Water Filter, 500 GPD
Filter: The iSpring RO500-BN is an under-sink, corded-electric reverse osmosis system with a tankless design and a listed capacity of 500 GPD. Its stated 2:1 pure-to-drain ratio and up-to-0.4-gpm flow target lower wastewater and quicker filling, while customer feedback is mixed on reliability and flow.
At a glance
- Tankless under-sink format is intended to preserve storage space beneath the sink.
- The manufacturer claims up to 500 GPD output and up to 0.4 gallons per minute, but customer accounts differ on perceived flow.
- The stated 2:1 pure-to-drain ratio describes the claimed water efficiency, not a measured result for every installation.
- The listing claims NSF 58 certification for TDS reduction and up to 99% reduction of over 1,000 contaminants. These are manufacturer claims, not independently verified here.
Reference price: $625.06
Price checked: Nov 14, 2026
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Pros and cons
Pros
- Tankless construction avoids a separate storage tank and is described as compact for under-sink placement.
- A brushed nickel faucet is identified in the title, and an ancillary faucet appears in the included-components listing.
- The manufacturer describes an automatic 20-second membrane rinse after 24 hours without use.
Cons
- It requires a corded electrical connection as well as under-sink installation.
- The listed 0.4-gpm maximum and 500 GPD rating may not match every buyer's expectations for everyday dispensing speed.
Technical specifications
19 specifications| Brand | iSpring |
|---|---|
| Model | RO500-BN |
| Purification method | Carbon Block, Reverse Osmosis |
| Special features | Tankless, Water Saver Technology |
| NSF certification claim | NSF 58 certified for TDS reduction |
| Rated daily output | 500 GPD |
|---|---|
| Maximum flow rate | 0.4 gpm |
| Pure-to-drain ratio | 2:1 |
| Supported water TDS level maximum | 750 |
| Operating pressure range | 15-70 psi |
| Lower temperature range | 41 °F |
| Upper temperature rating | 100 °F |
| Filter media listed | Reverse Osmosis Membrane & Carbon Block + PP Composite Filter & Post Carbon Filter |
|---|---|
| Filter life cycle | 2 years |
| Automatic membrane rinse claim | If this system is not used after 24 hours, it will rinse the RO MEMBRANE for 20 seconds |
| Power configuration | Corded Electric |
|---|---|
| Installation type | Under Sink |
| Dimensions listed | 17.5"L x 5.2"W x 16.25"H |
| Weight listed | 21 pounds |
What to know before buying
Listing details to confirm
Listing details are contradictory or unconfirmed: the model field identifies RO500-BN while another model-number field says RO500, and the title calls the faucet brushed nickel while another description calls it smart with TDS monitoring. The listed 500 gallons capacity is not clearly reconciled with the separate 500 GPD daily-output claim. Confirm the selected configuration, faucet functions, output rating, and installation fit before purchase.
What’s in the box
Included- Ancillary faucet
Who is it for?
A good fit for
- Households seeking an under-sink reverse osmosis system with no storage tank.
- Buyers with room for a corded unit and a compatible under-sink installation.
- Users who prioritize the listed water-saving ratio and want a dedicated faucet.
Less suited to
- Buyers needing a countertop or non-electric filtration system.
- Shoppers who require a guaranteed flow rate or reliability level, since customer feedback reports mixed experiences.
Customer reviews on Amazon
- 5 stars
82% 82% - 4 stars
9% 9% - 3 stars
2% 2% - 2 stars
1% 1% - 1 star
6% 6%
Customer feedback highlights easy installation and maintenance, compact placement under the sink, and favorable impressions of water taste and quality. Some users describe a noticeable TDS reduction, but that is an individual report rather than a guaranteed result. Reliability and water flow draw mixed reactions. This matters because the advertised 500 GPD and 0.4-gpm figures are listing claims, while real-world satisfaction with flow is not uniform.
Positive themes
- Customers report that installation and maintenance are easy.
- Customers praise the compact under-sink fit and water taste and quality.
Mixed feedback
- Customer feedback is mixed on reliability, including reports that some units stop working.
- Opinions on water flow vary, with some praising it and others finding it lower than expected.
Frequently asked questions
Does the RO500-BN need a storage tank?
The listing describes it as tankless, so it is designed without a separate storage tank.
What output and flow rate does the listing claim?
It claims up to 500 GPD and lists a maximum flow rate of 0.4 gpm. Customer feedback on perceived flow is mixed.
What faucet is included?
An ancillary faucet is listed as an included component, and the title specifies brushed nickel. The listing also describes a smart faucet with TDS monitoring elsewhere, so confirm the exact faucet configuration for the selected listing.
What are the installation requirements?
It is listed for under-sink installation and uses corded electric power. Check the listed dimensions and available space before buying.
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