SLF Water Filtration Comparison · 2026
VIVA21 6-Stage Alkaline RO
Recommended
APEC RO-PH90
Recommended for shoppers who prefer proven traditional RO hardware but want higher 90 GPD output and alkaline remineralization.
Depends on Your Priorities
The measurable advantages are split in this matchup, so the better choice depends on the features you value most.
RO Performance & Ownership
Compare RO output, filtration stages, remineralization, contaminant evidence, certifications and ownership cost.
Certification & Testing
Exact-model evidence recorded in the SLF database.
| Evidence | VIVA21 6-Stage Alkaline RO | APEC RO-PH90 |
|---|---|---|
| NSF/ANSI 58 | Certified / Listed | Certified / Listed |
| NSF/ANSI/CAN 372 | Manufacturer Claimed | — |
| WQA | Certified / Listed | Certified / Listed |
Which Is Right for You?
VIVA21 6-Stage Alkaline RO
Best for: Households wanting a traditional under-sink RO system with remineralization and a dedicated storage tank.
Consider if: Budget Under $300, Want Remineralization
APEC RO-PH90
Best for: Homeowners wanting broad reverse-osmosis contaminant reduction plus minerals added back for taste and pH, without moving to an electronic tankless system.
Consider if: Want Remineralization, Want TDS Display
Our Recommendation
VIVA21 6-Stage Alkaline RO
A compelling value-oriented alternative to higher-priced tankless RO systems for households that don't mind giving up cabinet space for a conventional storage tank.
APEC RO-PH90
A strong premium traditional RO choice for households that want alkaline remineralized water and established certification without electronics or a tankless design.
The Short Answer
Choose the VIVA21 6-Stage if you want an affordable traditional under-sink RO system with alkaline remineralization and stronger certification positioning than many budget RO systems.
Choose RO-PH90 for 90 GPD plus alkaline remineralization and WQA Gold Seal certification; choose ROES-50 for lower cost or a Waterdrop/iSpring tankless model for much faster production.
Water Filter Comparison FAQs
Answers are generated from the current SLF product records for these two systems.
Which is better, VIVA21 6-Stage Alkaline RO or APEC RO-PH90?
There is no single winner for every household. The current SLF records show meaningful trade-offs, so the better choice depends on filtration, output, installation, features and ownership cost.
Which system has the higher daily filtration capacity?
APEC RO-PH90 has the higher rated output: 90 GPD versus 50 GPD.
Which system offers remineralization?
Both systems are listed as yes for remineralization in the current SLF records.
Which system has the lower MSRP?
VIVA21 6-Stage Alkaline RO has the lower MSRP in the current SLF records at $339.99, compared with $409.99 for the other system.
Do both systems require a plumbing connection?
VIVA21 6-Stage Alkaline RO: Yes. APEC RO-PH90: Yes.
Which system is more renter friendly?
VIVA21 6-Stage Alkaline RO: No. APEC RO-PH90: No. Check lease and plumbing-modification rules before installing an under-sink system.
What certifications are listed for these systems?
VIVA21 6-Stage Alkaline RO: Manufacturer states VIVA21 is WQA Gold Seal certified to NSF/ANSI 58 for RO system performance and NSF/ANSI 372 for lead-free materials. SLF has not yet independently located the model in WQA's public directory; retain manufacturer-source status pending direct WQA verification. APEC RO-PH90: APEC identifies RO-PH90 as WQA Gold Seal certified. Retail listings also describe NSF-certified filter components. Avoid implying every individual 1,000+ contaminant claim has a separate NSF certification unless supported by the performance data sheet.
How do estimated annual filter costs compare?
VIVA21 6-Stage Alkaline RO: $99.99. APEC RO-PH90: $74.99. Actual replacement timing and prices can vary.