Hydrologic · Under-Sink RO Systems
Hydro Logic Stealth-RO150 Reverse Osmosis Filter
Lower-concern RO filter; standard materials unlikely to leach PFAS, but brand offers no transparency on membrane source or testing.
The Hydro Logic Stealth-RO150 uses typical reverse-osmosis construction, polyamide membrane, activated carbon, and sediment cartridges, none of which are common PFAS-risk categories. RO systems generally don't require water-repellent or stain-resistant coatings.
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RO membrane (polyamide), carbon & sediment filters, plastic housing
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
Why this grade
No PFAS disclosure
No public statement about PFAS in this product.
Safe base material
Made from a material with no inherent PFAS use (ceramic, mineral, or natural fiber).
The full breakdown
What it's made of and why it matters
The Stealth-RO150 uses a polyamide thin-film composite (TFC) RO membrane, which is the industry standard and chemically stable under normal operating pressure and temperature. Carbon and sediment pre-filters trap particles and chlorine before water reaches the membrane, extending its life. The housing is plastic (likely polypropylene or acrylic), which does not contact treated water under pressure for extended periods in typical under-sink designs, minimizing leaching risk. Polyamide membranes do not leach monomers or problematic chemicals into permeate water at normal operating conditions.
The brand's record and disclosure
Hydro Logic (also marketed as General Hydroponics) does not publish transparency reports on membrane sourcing, manufacturing testing, or third-party certifications on this model. The brand offers no public stance on PFAS testing or chemical disclosure. Industry standard suggests membranes are sourced from major OEM suppliers (Filmtec, Koch, Hydranautics), but Hydro Logic does not specify. No recalls or contamination incidents are on record for this product line.
How it compares in its category
The Stealth-RO150 is a mid-range consumer RO system with modest flow rate (150 GPD) and standard filtration stages. Competitors in the same price tier (Aqua-Pure, Watts, DuPont) also do not routinely disclose membrane sourcing; certification to NSF/ANSI 42, 53, 58 is common but absent from Hydro Logic marketing. Under-sink RO systems as a category have a strong safety record for materials; the main variation is membrane quality and pre-filter performance, not housing or membrane leaching hazards.
If you buy it
Replace pre-filters every 6-12 months depending on source water quality; failure to do so reduces flow and increases sediment bypass. Replace the RO membrane every 2-3 years or when flow drops noticeably. Do not expose the plastic housing to temperatures above 40 degrees C (104 F) or direct sunlight; store filters in a cool, dry cabinet. Flush the system for 3-5 minutes after installation and monthly if not in daily use to prevent bacterial or mold growth in the lines.
Beyond PFAS: other things we checked
Established hazard classes for this product type, assessed from public information. These never change the PFAS grade; a Likely flag caps the Verdict at “Buy with care.”
Bacterial growth in storage tank (if equipped) or idle lines
Under-sink RO systems with storage tanks can develop biofilm if not flushed regularly or if tank is not food-grade and UV-treated. Hydro Logic does not specify tank material or anti-microbial design for the Stealth-RO150 in public documentation.
Plastic housing off-gassing or leaching from carbon pre-filters
No reported issues with polyamide or polypropylene housing in standard RO units. Carbon filters themselves do not off-gas under normal operating conditions, and activated carbon is inert.
Membrane degradation or fragment release
Polyamide membranes can degrade if exposed to chlorine (should be removed by pre-filter), high temperature, or excessive pressure. Degradation would reduce efficiency rather than create acute hazard, but long-term use without pre-filter replacement increases risk.
Leachables from plastic fittings or tubing
Standard food-grade polyethylene or polypropylene fittings and tubing in RO systems are not known to leach under normal water temperature and pressure conditions. Hydro Logic does not disclose material specifications for fittings.
Lack of third-party certification transparency
Hydro Logic does not advertise NSF/ANSI certification for the Stealth-RO150, which is common for budget-tier models. Absence of certification is a disclosure gap, not a confirmed hazard, but suggests limited independent testing on contaminant reduction claims.
What we don’t know
This grade is a model-based estimate from public materials, coatings, and brand disclosure at 72% confidence. It is not a lab result.
No independent PFAS lab test is on record for this exact product. A lab test could move the score in either direction.
The brand has not made a specific, verifiable PFAS-free statement, so part of this score reflects that missing disclosure rather than a confirmed material.
Formulations and coatings change between production runs. Always check the current label before buying.
Safer alternatives in Under-Sink RO Systems
Aqua Guard
AQUASURE Premier Series 75 GPD Under Sink Reverse Osmosis Water Filtration System
RO membrane, carbon filters, stainless steel housing
Lower-concern RO system; standard filtration materials carry minimal PFAS risk, but brand is silent on the topic.
✓Bare metal or glass, no coating at all
Aqua Guard
AquaTru Under Sink Under Sink
Multi-stage filter cartridges (activated carbon, ion exchange resins)
Lower PFAS concern for standard under-sink filter use, but verify current cartridge specs before purchase.
✓Brand claims PFAS-free (unverified)
Home Master
TM Undersink Reverse Osmosis Water Filter System
Reverse osmosis membrane, carbon, sediment filters, stainless steel housing
Lower-concern RO filter system; no known PFAS materials identified, but brand makes no explicit PFAS commitment.
✓Bare metal or glass, no coating at all
More under-sink ro systems grades
How we score: every product runs through the same public 0–100 rubric based on materials, coatings, brand disclosure, lab findings, and recalls. See the full methodology → Spotted a mistake? Report an error.