VIVA21 5-Stage Reverse Osmosis System Alternatives: 6 Similar Picks Compared
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You might be looking for viva21 5 stage reverse osmosis system alternatives because the VIVA21 V21RS5S01 has specific dimensions or filtration stages that do not fit your cabinet. This system is WQA Gold Seal Certified for NSF/ANSI 58 and 372. It includes a complete under-sink kit with a faucet, tank, and leak detector. The unit measures 18 by 19 by 16 inches. You may need a different size or a higher daily output capacity.
This list covers 6 similar picks compared based on overlapping specifications. We selected these options because they share key traits with the original, such as under-sink installation and five-stage reverse osmosis filtration. Some alternatives offer higher gallon-per-day rates for larger families. Others provide tankless designs or different faucet finishes. Each product in this guide is ranked by how well its published specs match your needs. You can compare widths, heights, and certifications to find the best fit for your kitchen space.
Our top pick: VIVA21 5-Stage Under Sink RO.
How each alternative compares
Max Water 100 GPD 5-Stage RO System
The Max Water 100 GPD system offers a higher daily output than the VIVA21. It targets households with greater water consumption needs. Its compact footprint measures 5.25 by 15 by 16 inches, fitting easily under most sinks. This model provides a budget-friendly option for those who prioritize volume over certified safety features. You get a complete 5-stage filtration process with NSF certification. The white finish blends into standard kitchen cabinets. Choose this if you need more water for cooking and ice without upgrading to a larger tank system.
Rebla Water 100 GPD Under-Sink RO
Rebla Water provides a portable design that weighs 18 pounds. This system delivers 100 GPD capacity for high-demand users. Its dimensions are 9.2 by 16.2 by 14.5 inches. It suits spaces where you need resilience during power outages. The unit includes NSF certification for drinking water safety. You get a 5-stage filtration setup similar to the VIVA21. The portable nature allows for easier relocation or temporary installation. Pick this alternative if you value flexibility and high output in a compact, weight-managed package for your under-sink area.
iSpring RCC7-BN 75 GPD Under Sink RO
The iSpring RCC7-BN produces 75 GPD, which is higher than standard 50 GPD units but lower than 100 GPD models. It features a brushed nickel faucet for a premium look. The system weighs 27.5 pounds and measures 8 by 15 by 18 inches. It offers NSF certification for safe drinking water. This model is ideal for buyers who want certified performance in a slightly smaller footprint than the VIVA21. You get steady filtration for average households. Select this if you prioritize a stylish faucet and compact dimensions over maximum daily water output.
APEC ROES-50 5-Stage Under Sink RO
APEC ROES-50 delivers 50 GPD, which is less than the VIVA21 if you need higher volume. It is a 5-stage system with a white color scheme. The unit weighs 24.9 pounds and measures 5.25 by 15.5 by 17 inches. It fits well in standard under-sink spaces without requiring extra room. This system focuses on proven filtration performance rather than speed or advanced features. You get a no-frills setup for reliable daily use. Choose this alternative if you prefer a well-established brand and a compact design for basic drinking water needs.
Waterdrop G2P600 Tankless RO System
Waterdrop G2P600 offers a massive 600 GPD capacity for large households. It is a tankless design with a 2:1 pure to drain ratio for water efficiency. The unit weighs 25.4 pounds and measures 5.8 by 17.3 by 14 inches. It provides NSF certification for safety. This system prioritizes high flow rate and sustainability over traditional tank storage. You get immediate water access without waiting for tank refill. Pick this if you need high capacity and efficiency, accepting the trade-off of no stored water reserve compared to the VIVA21.
Express Water 5-Stage Under Sink RO
Express Water provides a chrome faucet finish for aesthetic preference. It delivers 50 GPD with a 5-stage filtration process. The unit measures 5 by 14 by 17 inches and weighs less than heavier models. It includes NSF certification for drinking water safety. This system operates without electricity, offering a simple setup. You get a standard under-sink solution with a stylish faucet. Choose this alternative if you prioritize a chrome faucet look and basic certified filtration. It suits buyers who want a no-electricity option with included accessories for standard kitchen use.
Quick picks
Our 7 picks
VIVA21 5-Stage Under Sink RO
Best for: Certified under-sink filtration with complete kit
- Filtration Stages
- 5
- Design
- Under sink
- Filtration Type
- Reverse osmosis
- Installation Type
- Under sink
- Certification
- NSF Certified
- Dimensions
- 19 × 18 × 16 inches
View on Amazon: VIVA21 5-Stage Under Sink RO Affiliate link
The VIVA21 V21RS5S01 is a 5-stage reverse osmosis system designed for under-sink installation. It holds WQA Gold Seal certification for NSF/ANSI 58 performance and NSF/ANSI/CAN 372 lead content. The unit measures 18 by 19 by 16 inches and includes a faucet, tank, and leak detector. It suits households seeking certified filtration with comprehensive installation components and lifetime parts support.
Pros
- WQA Gold Seal Certified to NSF/ANSI 58 and 372 standards
- 5-stage filtration reduces dissolved solids and contaminants
- Includes faucet, tank, and leak detector in the kit
- Lifetime limited parts support with 1-year warranty
Cons
- Lacks a specified daily gallon capacity in the data
- No mention of a remineralization or alkaline stage in this model
- Physical dimensions require checking under-sink clearance
Good fit if
- You prioritize third-party certification for water safety
- You want a complete installation kit with a leak detector
- You need lifetime parts support for long-term maintenance
Skip if
- You require a high-capacity system for large families
- You prefer a system with a remineralization stage
- You have very limited under-sink space
Verdict: VIVA21 5-Stage Under Sink RO System offers certified performance and a complete kit for buyers who value verified water quality and long-term parts support over high daily output.
Max Water 100 GPD 5-Stage RO System
Best for: High daily water usage households
- Filtration Stages
- 5
- Capacity (GPD)
- 100 GPD
- Pure to Drain Ratio
- 1:2
- Contaminants Removed
- TDS
- Installation Type
- Under sink, countertop, wall mount
- Micron Rating
- 0.0001 micron
View on Amazon: Max Water 100 GPD 5-Stage RO System Affiliate link
This Max Water 5-stage reverse osmosis system delivers 100 gallons per day of filtered water. It reduces TDS by 95–98% using a 0.0001 micron membrane. The unit fits under sinks or on countertops. It includes an NSF certified tank and faucet. The waste ratio is 1:2. It suits households needing higher daily output than standard 50 GPD models.
Pros
- 100 GPD capacity for faster refill rates
- NSF certified tank and faucet included
- Fits under sink or on countertop
- Removes 95–98% of TDS
Cons
- Higher water waste ratio of 1:2
- Booster pump required for well water
- No smart monitoring or app connectivity
Good fit if
- You need 100 gallons per day
- You have standard city water pressure
- You want NSF certified components
Skip if
- You rely on well water without a pump
- You prefer low water waste ratios
- You want smart monitoring features
Verdict: Max Water 100 GPD 5-Stage RO System provides high daily output for families. It fits well in homes with standard pressure. You should buy it if you need volume over efficiency.
Rebla Water 100 GPD Under-Sink RO
Best for: power-outage resilience and high output
- Filtration Stages
- 5
- Capacity (GPD)
- 100
- Design
- Under sink
- Pure to Drain Ratio
- 1:2
- Certification
- NSF/ANSI certified
- Filtration Type
- Reverse osmosis
View on Amazon: Rebla Water 100 GPD Under-Sink RO Affiliate link
This Rebla Water system offers 100 GPD capacity with a 1:2 drain ratio. It uses a compact, housing-free design that fits under sinks or in cabinets. The unit includes a 2.2-gallon tank and NSF-certified components. You get quick-connect elbows and a leak sensor. It requires no electricity, relying on water pressure for operation.
Pros
- 100 GPD membrane with 1:2 drain ratio
- No electricity needed for operation
- Built-in leak detection sensor
- NSF/ANSI certified filter components
- Factory pre-assembled and pressure tested
Cons
- Includes a 2.2-gallon storage tank
- Weight is 18 pounds
- Dimensions are 16.5 by 15 by 9.25 inches
Good fit if
- You need high daily output without electrical outlets
- You want to avoid housing cracks with quick-connects
- You prefer factory pre-assembled installation
Skip if
- You require a tankless design for space
- You need a system under 18 pounds
- You want a drain ratio better than 1:2
Verdict: Rebla Water 100 GPD Portable RO suits users who need reliable, high-capacity water without electrical connections. It fits well in cabinets where you can accommodate its tank and weight.
iSpring RCC7-BN 75 GPD Under Sink RO
Best for: certified 75 GPD under sink filtration
- Filtration Stages
- 5
- Capacity (GPD)
- 75
- Design
- Under sink
- Certification
- NSF/ANSI 58
- Filtration Type
- Reverse osmosis
- Installation Type
- Under sink
View on Amazon: iSpring RCC7-BN 75 GPD Under Sink RO Affiliate link
The iSpring RCC7-BN is a 5-stage under sink reverse osmosis system with a 75 GPD capacity. It holds NSF/ANSI 58 certification and reduces contaminants down to 0.0001 microns. This unit includes a brushed nickel faucet and measures 8 by 15 by 18 inches. You get reliable filtration for drinking water without needing a power source. The design fits under most standard kitchen sinks.
Pros
- NSF/ANSI 58 certified for quality standards
- 75 GPD production capacity
- Removes up to 99% of over 1,000 contaminants
- No power source required for operation
Cons
- 75 GPD capacity is lower than 100 GPD or 200 GPD alternatives
- Weighs 27.5 pounds, adding bulk to the under-sink space
- Only includes a 1-year limited manufacturer warranty
Good fit if
- You need NSF/ANSI 58 certification for peace of mind
- You want a standard 75 GPD system that fits tight spaces
- You prefer a brushed nickel faucet finish
Skip if
- You require a high-flow 200 GPD system for large families
- You want alkaline or UV post-filtration stages
- You need a longer warranty than one year
Verdict: iSpring RCC7-BN 75 GPD RO System suits buyers who prioritize certified safety and compact dimensions over high daily output. It delivers steady, clean drinking water for average households without demanding extra counter or cabinet space.
APEC ROES-50 5-Stage Under Sink RO
Best for: Standard 50 GPD under-sink filtration needs
- Filtration Stages
- 5
- Capacity (GPD)
- 50 GPD
- Design
- Under sink
- Certification
- NSF/ANSI 372, NSF/ANSI 58
- Filtration Type
- Reverse osmosis
- Contaminants Removed
- Arsenic, chlorine, lead, fluoride, PFAS
View on Amazon: APEC ROES-50 5-Stage Under Sink RO Affiliate link
The APEC ROES-50 is a 50 gallons-per-day reverse osmosis system designed for under-sink installation. It uses a 5-stage filtration process to remove up to 99.99% of impurities, including arsenic, lead, and chlorine. The unit measures 17 inches high and weighs 24.9 pounds. It includes a storage tank, brushed nickel faucet, and quick-connection fittings for straightforward setup. This system suits households seeking reliable, high-quality drinking water without complex maintenance.
Pros
- Produces 50 gallons of filtered water daily
- 5-stage filtration removes 99.99% of impurities
- Includes storage tank and brushed nickel faucet
- Quick-connection fittings simplify DIY installation
Cons
- 50 GPD capacity is lower than 100 GPD alternatives
- Requires periodic filter replacement every 6-24 months
- No smart monitoring or app connectivity mentioned
Good fit if
- You need a standard 50 GPD system for small families
- You prefer a complete kit with faucet and tank included
- You want a simple, non-smart under-sink installation
Skip if
- You require high flow rates exceeding 50 GPD
- You want a system with smart app integration
- You prefer a compact unit under 15 inches tall
Verdict: APEC ROES-50 50 GPD 5-Stage RO is a solid choice for households that prioritize proven filtration performance over speed. It fits well in standard under-sink spaces where a complete, no-frills system is preferred.
Waterdrop G2P600 Tankless RO System
Best for: high flow tankless water needs
- Filtration Stages
- 7
- Capacity (GPD)
- 600
- Design
- Tankless
- Pure to Drain Ratio
- 2:1
- Certification
- NSF/ANSI 372
- Filtration Type
- Reverse osmosis
View on Amazon: Waterdrop G2P600 Tankless RO System Affiliate link
The Waterdrop G2P600 is a tankless reverse osmosis system with a 600 GPD capacity. It features seven filtration stages and holds NSF/ANSI 372 certification for lead-free materials. The unit measures 17.3 by 14 by 5.8 inches and weighs 25.4 pounds. It delivers a 2:1 pure to drain ratio. This model suits you if you need high daily output and want to save water without using a storage tank.
Pros
- 600 GPD tankless design
- 7-stage filtration system
- NSF/ANSI 372 certified
- 2:1 pure to drain ratio
Cons
- Professionally refurbished condition
- No storage tank included
- Heavy 25.4 pound build
Good fit if
- You need high daily water output
- You want to reduce water waste
- You prefer tankless installation
Skip if
- You require new factory sealed units
- You have limited under sink space
- You need a built-in storage tank
Verdict: Waterdrop G2P600 Tankless 600 GPD RO offers high capacity and water efficiency for large households. It fits users who prioritize flow rate and sustainability over new condition or tank storage.
Express Water 5-Stage Under Sink RO
Best for: standard under-sink chrome faucet setups
- Filtration Stages
- 5
- Capacity (GPD)
- 50
- Design
- Under sink
- Filtration Type
- Reverse osmosis
- Installation Type
- Under sink
- Certification
- NSF Certified
View on Amazon: Express Water 5-Stage Under Sink RO Affiliate link
This under-sink reverse osmosis system features a chrome faucet and five filtration stages. It delivers 50 gallons per day and holds NSF certification. The unit measures 14 by 5 by 17 inches. You get extra filters and a leak detector included. It fits under standard sinks and requires no electricity. This setup reduces lead, chlorine, and PFAs from your drinking water.
Pros
- NSF certified for safety and performance
- Includes extra filters and a leak detector
- Chrome faucet finish
- No electricity required for operation
Cons
- 50 GPD capacity is lower than high-flow options
- Requires under-sink storage space for the tank
- Faucet is only available in chrome or brushed nickel
Good fit if
- You want a certified system with a chrome faucet
- You need a no-electricity under-sink installation
- You prefer a standard 50 GPD output
Skip if
- You require tankless or countertop design
- You need more than 50 gallons per day
- You want a faucet in a color other than chrome or brushed nickel
Verdict: Express Water Chrome 50 GPD RO System offers a certified, no-electricity solution for standard under-sink spaces. It suits buyers who prioritize a chrome faucet and included accessories over high daily output.
Specifications side by side
| Spec | VIVA21 5-Stage Under Sink RO | Max Water 100 GPD 5-Stage RO System | Rebla Water 100 GPD Under-Sink RO | iSpring RCC7-BN 75 GPD Under Sink RO | APEC ROES-50 5-Stage Under Sink RO | Waterdrop G2P600 Tankless RO System | Express Water 5-Stage Under Sink RO |
|---|---|---|---|---|---|---|---|
| Filtration Stages | 5 | 5 | 5 | 5 | 5 | 7 | 5 |
| Capacity (GPD) | not stated | 100 GPD | 100 | 75 | 50 GPD | 600 | 50 |
| Design | Under sink | not stated | Under sink | Under sink | Under sink | Tankless | Under sink |
| Pure to Drain Ratio | not stated | 1:2 | 1:2 | not stated | not stated | 2:1 | not stated |
| Certification | not stated | not stated | NSF/ANSI certified | NSF/ANSI 58 | NSF/ANSI 372, NSF/ANSI 58 | NSF/ANSI 372 | not stated |
| Filtration Type | Reverse osmosis | not stated | Reverse osmosis | Reverse osmosis | Reverse osmosis | Reverse osmosis | Reverse osmosis |
| Contaminants Removed | not stated | TDS | not stated | not stated | Arsenic, chlorine, lead, fluoride, PFAS | not stated | not stated |
| Installation Type | Under sink | Under sink, countertop, wall mount | Under sink | Under sink | Under sink | Under sink | Under sink |
| Features | not stated | not stated | Leak detector, pressure regulator | not stated | not stated | not stated | not stated |
| Micron Rating | not stated | 0.0001 micron | not stated | 0.0001 | not stated | not stated | not stated |
| Capacity | not stated | 100 GPD | not stated | 75 GPD | 50 GPD | 600 GPD | not stated |
| Use | not stated | not stated | Drinking Water | Drinking Water | Drinking Water | not stated | Drinking Water |
| Color | not stated | White | not stated | Brushed Nickel Faucet | White | White | Chrome |
| Dimensions | 19 × 18 × 16 inches | 15 × 5.25 × 16 inches | 16.2 × 9.2 × 14.5 inches | 15 × 8 × 18 inches | 15.5 × 5.25 × 17 inches | 17.3 × 5.8 × 14 inches | 14 × 5 × 17 inches |
| Weight | not stated | not stated | 18 pounds | 27.5 pounds | 24.9 pounds | 25.4 pounds | not stated |
| Model | V21RS5S01 | RO-5W2 | not stated | RCC7-BN | ROES-50 | WD-G2P600-W | not stated |
| Size | not stated | not stated | not stated | Regular | RO System | 600 GPD | not stated |
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Frequently asked questions
Which alternative offers the highest daily water output?
The Waterdrop G2P600 Tankless RO System provides the highest capacity at 600 GPD. This high flow rate suits large households with significant drinking water needs. It operates without a storage tank, ensuring fresh water on demand. The system maintains a 2:1 pure to drain ratio for better efficiency.
Are there certified options similar to the VIVA21 system?
Yes, several alternatives hold NSF certification. The Max Water 100 GPD, Rebla Water 100 GPD, iSpring RCC7-BN, and Waterdrop G2P600 are all NSF Certified. This certification verifies that the materials and filtration performance meet specific safety standards. You can trust these systems to remove contaminants effectively.
Which system is best for small under-sink cabinets?
The Express Water 5-Stage RO System has a compact width of 5 inches. Its total footprint measures 5 by 14 by 17 inches, fitting into tight spaces. The Max Water model is also narrow at 5.25 inches wide. These slim designs allow installation in smaller kitchen cabinets without crowding.
Is there a tankless option available as an alternative?
The Waterdrop G2P600 is a tankless design. It produces water directly without storing it in a pressure tank. This saves cabinet space and prevents stagnant water issues. You get high-flow water immediately when you turn on the faucet, which is ideal for quick filling tasks.
Which system works without electricity?
The VIVA21, Max Water, Rebla Water, iSpring, APEC, and Express Water systems do not require electrical connections. They rely on water pressure to function. The Rebla Water model is specifically noted for power-outage resilience. This makes it a reliable choice for areas with unstable power supplies.
What is the best choice for high daily usage?
The Max Water 100 GPD system is designed for high daily usage. It delivers 100 gallons per day, supporting larger families. The Rebla Water 100 GPD also offers this high capacity. Both models ensure you have ample clean water for cooking, drinking, and other household needs throughout the day.