Nitrate is a contaminant you should treat as a specific performance requirement—not assume an RO system removes just because it reduces total dissolved solids (TDS). The product information below does not provide a nitrate-specific reduction claim or certified nitrate performance data for any of these five systems. Each may be worth considering as an RO option, but before buying for nitrate, check the manufacturer’s performance data sheet or certification listing for an explicit nitrate-reduction claim that matches your water conditions.
Our comparison focuses on the systems’ stated features, filtration claims, installation style, and practical tradeoffs. If nitrate is a concern in your tap or well water, test your water and confirm that the selected system is certified or otherwise documented to reduce nitrate.
Quick Comparison
| System | Type | Standout feature | Nitrate information supplied |
|---|---|---|---|
| Waterdrop G3P600 Tankless RO System | Under-sink, tankless | 600 GPD capacity and smart display faucet | No nitrate-specific reduction claim listed |
| DREO Countertop RO Filtration System | Countertop | Portable-style setup with TDS and filter-life displays | No nitrate-specific reduction claim listed |
| APEC ROES-PH75X | Under-sink, tank-style | Alkaline remineralization stage | No nitrate-specific reduction claim listed |
| iSpring RCC7P-AK | Under-sink, pump-assisted | Booster pump for homes with low water pressure | No nitrate-specific reduction claim listed |
| iSpring RCC7AK-BLK | Under-sink, tank-style | NSF/ANSI 58 certification and alkaline stage | No nitrate-specific reduction claim listed |
Our Picks: Best Reverse Osmosis System For Nitrate Removal reviews
Waterdrop G3P600: A High-Capacity Tankless Option
The Waterdrop G3P600 is an under-sink RO system designed to save cabinet space by going tankless. Its stated production capacity is 600 gallons per day, and the smart faucet includes a TDS monitor and filter-life indicator. The product information also lists NSF/ANSI 58 certification for TDS reduction, NSF/ANSI 42 testing and certification for chlorine, taste, and odor reduction, and NSF/ANSI 372 certification for lead-free materials.
Waterdrop lists a range of other contaminants its system was tested to reduce, but nitrate is not among the claims provided. TDS readings also cannot tell you whether nitrate is present or whether it has been reduced, so the faucet display should not be treated as a nitrate test. For a nitrate-focused purchase, ask the manufacturer for a performance sheet or certification listing that specifically covers nitrate.
The tankless layout may suit a household that wants more under-sink room than a traditional tank system allows. The product dimensions are listed as 18.12 by 5.67 by 17.72 inches, and it needs under-sink electricity. Its stated pure-to-drain ratio is 2:1. That makes it a feature-rich choice, but it has more installation requirements than a countertop unit.
Pros:
- Tankless design helps preserve cabinet space.
- Smart faucet displays TDS and filter-life information.
- Stated capacity of 600 gallons per day.
- Specified NSF/ANSI certifications cover TDS, chlorine-related reduction, and lead-free materials.
Cons:
- The supplied product information does not list nitrate reduction.
- Requires under-sink power and careful cabinet measurement.
Verdict: Consider the G3P600 if you want a space-saving, high-capacity RO system, but choose it for nitrate concerns only after confirming a nitrate-specific performance claim.
DREO Countertop RO: A No-Under-Sink Alternative
The DREO is a countertop reverse osmosis system, so it offers an alternative to installing filters and a faucet under your sink. Its product description calls it a 7-in-1 system and says it was tested by SGS to meet NSF/ANSI 58 standards. The listed reduction claims include PFOA, PFOS, chlorine, and fluoride, among other possible contaminants.
The product details supplied here do not spell out its full dimensions, capacity, filter replacement schedule, or a nitrate-reduction result. They also describe SGS testing against a standard, which is not the same wording as saying the complete system is certified for a particular contaminant. If you are buying specifically for nitrate, request documentation naming nitrate and showing the reduction performance.
A countertop design may appeal if you rent, want to avoid plumbing changes, or prefer not to give up under-sink space. In exchange, you will need room on the counter and should confirm the unit’s operating and maintenance requirements before choosing it. Its stated 3:1 pure-to-drain ratio is a useful point of comparison, but it does not establish nitrate removal.
Pros:
- Countertop format avoids an under-sink installation.
- Product information lists reduction claims for several contaminants, including PFOA and PFOS.
- Stated 3:1 pure-to-drain ratio.
- SGS testing is described in relation to NSF/ANSI 58 standards.
Cons:
- No nitrate-specific reduction claim is supplied.
- Available product details do not provide full capacity and maintenance specifications.
Verdict: The DREO may fit buyers who want a countertop RO setup, but its nitrate performance needs to be confirmed before it can be considered for nitrate treatment.
APEC ROES-PH75X: Under-Sink RO With Added Minerals
The APEC ROES-PH75X is a six-stage under-sink system with an alkaline remineralization stage. The supplied description lists a 75-gallon-per-day rating and says the system is designed to reduce chlorine, taste and odor, VOCs, fluoride, arsenic, lead, heavy metals, and many other impurities. It also states that the system is WQA certified and lists NSF certifications for standards 372 and 58.
The calcium stage is intended to add minerals back to the water after RO filtration. That may suit people who prefer the taste of remineralized water, but it does not replace checking the system’s contaminant-specific performance. Although the description mentions a broad range of impurities, it does not name nitrate as a tested or certified reduction claim.
This is a conventional under-sink system, so plan for cabinet space and a suitable water connection. Its stated feed-water pressure range is 40–85 psi, and its maximum listed TDS for feed water is 2,000 ppm. Those specifications can help you assess basic compatibility, but nitrate performance should be verified separately.
Pros:
- Six-stage design includes a calcium-based remineralization stage.
- Stated 75-gallon-per-day production rating.
- Product information lists NSF/ANSI 58 and 372 certifications and WQA certification.
- Provides stated feed-water pressure and TDS limits for compatibility checks.
Cons:
- No nitrate-specific reduction claim is listed.
- Requires under-sink installation and adequate incoming water pressure.
Verdict: The ROES-PH75X is a reasonable option to compare if you want under-sink filtration with remineralization, provided APEC confirms nitrate reduction for your intended use.
iSpring RCC7P-AK: A Pump-Assisted System for Lower Pressure
The iSpring RCC7P-AK is a six-stage under-sink RO system with an electric booster pump. The pump is intended to support filtration in homes with low water pressure, while the final alkaline stage adds minerals back to the filtered water. The supplied description also lists reduction claims for contaminants such as lead, chlorine, fluoride, arsenic, and PFAS.
The product information does not state a nitrate-specific reduction result. Its broad claim of reducing more than 1,000 contaminants should not be treated as proof of nitrate performance unless the manufacturer’s supporting documentation names nitrate. This distinction matters most when your water test has identified nitrate as a concern.
The pump may make this model a better fit than a standard system when household pressure is low, but it also means the setup needs power. The included adapter is listed as compatible with 100–240V and 50/60Hz power. The alkaline stage is a taste-related feature; it does not add nitrate-specific treatment.
Pros:
- Booster pump is designed for homes with low water pressure.
- Six-stage filtration includes alkaline remineralization.
- Product information lists reduction claims for lead, fluoride, arsenic, and PFAS.
- Power adapter is listed for a broad voltage and frequency range.
Cons:
- No nitrate-specific reduction claim is supplied.
- The booster pump requires power and adds another component to the system.
Verdict: Choose the RCC7P-AK for its pump-assisted design if low water pressure is a concern, but verify nitrate performance before relying on it for that contaminant.
iSpring RCC7AK-BLK: Certified RO With a Black Faucet
The iSpring RCC7AK-BLK is a six-stage under-sink RO system with an alkaline remineralization filter and a black faucet. Its product details state that the system is NSF/ANSI 58 certified and list reductions for several contaminants, including TDS, lead, fluoride, asbestos, barium, cadmium, chromium, copper, and selenium. The description also says the system has three pre-filters before the RO membrane and a finishing filter.
The supplied certification claims are more specific than a general statement about filtration, but nitrate is not named in the performance details provided. Check the complete certification listing or manufacturer performance sheet for an explicit nitrate claim. The included black faucet may help the system match a kitchen with dark hardware, though faucet appearance does not affect treatment performance.
This model is a traditional under-sink choice rather than a tankless system. The manufacturer describes DIY installation support, quick-fitting connectors, and lifetime technical support. As with the other under-sink systems, check your cabinet space and installation needs before ordering. The alkaline stage is intended to restore minerals and change the water’s taste; it should not be confused with nitrate removal.
Pros:
- Product information states NSF/ANSI 58 certification.
- Lists reduction performance for several named contaminants.
- Alkaline stage adds minerals back after RO filtration.
- Includes a black faucet and describes DIY installation support.
Cons:
- No nitrate-specific reduction claim is included in the supplied details.
- Requires under-sink space and installation.
Verdict: The RCC7AK-BLK is a strong feature match for shoppers who want a certified under-sink RO system with remineralization, but nitrate use depends on confirming an explicit nitrate claim.
How to Choose a Reverse Osmosis System for Nitrate
Look for a nitrate-specific performance claim
Do not rely on a general RO label, a long list of contaminants, or a TDS-reduction certification alone. Check the full performance data sheet or certification listing for the exact system and filter configuration. It should name nitrate or nitrate-nitrogen and explain the reduction claim. If the manufacturer cannot provide that information, treat nitrate performance as unconfirmed.
Test your water before selecting a system
A water test helps you understand whether nitrate is present and whether other contaminants also need attention. This is especially important for private wells, where water quality can vary by location and over time. Use a qualified testing service or a suitable test method, then compare the result with the treatment system’s documented operating limits and reduction data.
Match the system to your installation
Under-sink systems usually require cabinet space and plumbing connections. Some models also need electricity, as with the Waterdrop tankless unit and the pump-assisted iSpring RCC7P-AK. A countertop system avoids under-sink installation but takes up counter space. Measure your area and check the product’s complete installation requirements before buying.
Check water pressure and system capacity
Incoming pressure can affect how an RO system works. The APEC model lists a feed-water pressure range, while the iSpring RCC7P-AK includes a booster pump intended for low-pressure homes. Compare your household conditions with the manufacturer’s requirements. Also consider how much filtered water your household needs; a stated daily capacity is a system specification, not a promise of nitrate reduction.
Understand the difference between TDS and nitrate testing
A TDS meter measures the total amount of dissolved material in water. It does not identify each substance or show whether nitrate is below a health-based limit. A low TDS reading is not a substitute for a nitrate test, and a faucet’s TDS display should be treated as a general indicator rather than a nitrate monitor.
Consider filter upkeep and water taste
RO systems use multiple filters that need replacement on a schedule set by the manufacturer and affected by water use and feed-water quality. Review filter availability and replacement instructions before choosing a model. If you prefer water with added minerals, an alkaline stage may appeal to you, but remineralization is separate from nitrate treatment.
Frequently Asked Questions
Does reverse osmosis remove nitrate?
Some RO systems may reduce nitrate, but performance depends on the exact system, filter condition, water chemistry, and operating conditions. Confirm that the manufacturer provides a nitrate-specific reduction claim for the model you plan to use.
Which system in this comparison has verified nitrate removal?
The supplied product information does not provide a nitrate-specific reduction claim for any of the five systems. That does not establish that a system cannot reduce nitrate; it means the claim should be verified through the manufacturer’s full performance data or certification listing before purchase.
Does NSF/ANSI 58 certification prove nitrate removal?
Not by itself. Check the certification listing and performance data for the exact contaminant claim. Certification for TDS reduction should not be assumed to certify nitrate reduction.
Can a TDS meter tell me if nitrate is in my water?
No. A TDS meter gives a broad measurement of dissolved material and does not identify nitrate. Use a nitrate-specific water test to check for nitrate.
Is a countertop RO system as suitable as an under-sink system?
That depends on your space, installation preferences, household water needs, and the system’s documented performance. The DREO is the countertop option in this group, while the other listed systems are designed for under-sink use. For nitrate, compare explicit performance data rather than choosing by format alone.
Should I choose an alkaline or remineralizing RO system for nitrate?
Choose a remineralizing stage based on your taste preference, not as a nitrate-treatment feature. Verify nitrate reduction separately for the complete system and filter configuration.
Final Recommendation
Based on the supplied product information, none of these systems can be named a verified best choice for nitrate removal because none includes a nitrate-specific performance claim. The Waterdrop G3P600 stands out for its tankless design and smart faucet, while the APEC and iSpring models offer under-sink filtration with remineralization, and the DREO provides a countertop format. For nitrate treatment, first test your water, then select a system whose manufacturer documentation explicitly confirms nitrate reduction for your conditions.