Under-sink reverse osmosis · checked 16 Oct 2026
Express Water RO System 5-Stage Reverse Osmosis
Model RO5DX · replacement parts FLTSED0501, FLTGAC0501, FLTCAR0501, FLTMEME50, FLTIN01PKQ
Lead:Brand claim onlyPFAS:not claimed
Each claim, checked
What the brand says, what a certification listing shows for this model, and where each fact comes from. We read listings; we do not test products.
- Certified (listing checked)The certifier’s public listing shows this claim for this model.
- Brand says certifiedThe brand says certified; IAPMO’s listing does not show it. NSF can be checked by hand.
- Brand claim onlyThe brand claims it without citing a certification.
| Contaminant | Brand claim | Standard | Certifier | Confirmed? | Source, date checked |
|---|---|---|---|---|---|
| Lead | “removing up to 99.99% of Lead, Chlorine, Fluoride, Nitrates, Calcium, Arsenic, Bacteria, and more” brand source | – | – | Brand claim — no certification cited | brand pagechecked 16 Oct 2026 |
| Total dissolved solids (TDS) | “Tested and Certified by NSF International against NSF/ANSI 58 for TDS Reduction - Models RO5DX & RO10DX” brand source | NSF/ANSI 58 | NSF (named by brand) | Brand says certified — not found in IAPMO’s listing; check NSF | IAPMO searched · check NSF’s listingchecked 16 Oct 2026 |
| Chlorine | Same statement as for Lead. brand source | – | – | Brand claim — no certification cited | brand pagechecked 16 Oct 2026 |
| Fluoride | Same statement as for Lead. brand source | – | – | Brand claim — no certification cited | brand pagechecked 16 Oct 2026 |
| Nitrate | Same statement as for Lead. brand source | – | – | Brand claim — no certification cited | brand pagechecked 16 Oct 2026 |
| Arsenic | Same statement as for Lead. brand source | – | – | Brand claim — no certification cited | brand pagechecked 16 Oct 2026 |
| Bacteria | Same statement as for Lead. brand source | – | – | Brand claim — no certification cited | brand pagechecked 16 Oct 2026 |
| Chloramine | “Chloramine | 3.17 | 0.01 | 99.68%” brand source | – | – | Brand claim — no certification cited | brand pagechecked 16 Oct 2026 |
| VOCs (volatile organic chemicals) | “Benzene | 50.88 | <0.01 | >99.98%” brand source | – | – | Brand claim — no certification cited | brand pagechecked 16 Oct 2026 |
| Uranium | “Uranium | 101 | <1 | >99.01%” brand source | – | – | Brand claim — no certification cited | brand pagechecked 16 Oct 2026 |
Filter changes, by the brand’s numbers
How often Express Water says to replace each part. Real filter life depends on how much water you use and what is in it.
| Part | Brand says replace every | Changes a year | Source, date checked |
|---|---|---|---|
| Pre-filters: sediment, GAC and carbon block (FLTSED0501, FLTGAC0501, FLTCAR0501) | 6 months“The Sediment, Granular Activated Carbon, Activated Carbon Block, Deionization and Alkaline Filters should be changed every 6 months.” | 2 | brand sourcechecked 16 Oct 2026 |
| RO membrane 50 GPD (FLTMEME50)The brand gives more than one figure for this part. | 12 months“The RO Membrane and Inline Post Activated Carbon Filter should be changed every 12 months”12–24 months“Inline PAC filter on the top every 12 months. Membrane every 12 to 24 months.” | 1 or 1 every 1–2 years | brand sourcechecked 16 Oct 2026brand sourcechecked 16 Oct 2026 |
| Inline post activated carbon filter (FLTIN01PKQ)The brand gives more than one figure for this part. | 12 months“The RO Membrane and Inline Post Activated Carbon Filter should be changed every 12 months”6 months“Pre & Post Filters SED, GAC, ACB, PAC ... Change Period* Every 6 months” | 1 or 2 | brand sourcechecked 16 Oct 2026brand sourcechecked 16 Oct 2026 |
Certification listings found
No IAPMO R&T listing matched this model when we searched on 16 Oct 2026.
Check it yourself
NSF’s and WQA’s terms don’t allow automated lookups, so these links open their public listings for this model:
- NSF listing search: RO5DX
- NSF listing search: Express Water
- WQA listing search: RO5DX
- WQA listing search: Express Water
- IAPMO R&T listing directory
What the brand says about certification
- “Tested and Certified by NSF International against NSF/ANSI 58 for TDS Reduction - Models RO5DX & RO10DX” source checked 16 Oct 2026
- “Express Water RO5DX and RO10DX have been tested according to NSF/ANSI 58 for reduction of the substances listed below.” source checked 16 Oct 2026
- “Our RO Systems are proven to reduce up to 99.99% of 158 impurities and Total Dissolved Solids (TDS)” source checked 16 Oct 2026
- “QFT Laboratory, LLC specializes in water filter testing following NSF/ ANSI standards 42, 53, 58, 61, P231, 401, and 473.” source checked 16 Oct 2026
Performance data sheet (names NSF International)