Duryn vs Phox: Choosing the Right Glass Water Filter Jug in the UK

Glass water filter jugs have become a popular alternative to bottled water - especially for households that want better-tasting tap water without relying on single-use plastic.

Two names that often come up in the UK are Phox and Duryn. Both offer countertop glass filter jugs, but they take different approaches to filtration design, materials, and everyday use.

At a glance: the core difference

Filtration approach: refillable granules vs precision cartridges

Phox V2 uses a refillable granule system. You open the cartridge, pour in loose filtration media, and choose different refill blends depending on whether you’re aiming for taste improvement, softening, or alkalinity adjustment. It’s designed around flexibility and reduced waste.

Duryn One uses a sealed, multi-layer cartridge, where the media is compressed into a fixed structure. This encourages water to pass through each filtration layer more evenly, aiming for more consistent filtration across the cartridge’s lifespan.

In short:

• Phox prioritises refill flexibility

• Duryn prioritises controlled filtration and consistency

What gets filtered — and how broad the scope is

Phox publishes filtration performance under EN 17093, which focuses on defined reductions such as chlorine, taste and odour, and certain metals (including lead and copper).

Duryn references NSF/ANSI 42 and 372 plus independent laboratory testing (IAPMO). Duryn positions its filtration as targeting a broader set of contaminants — including modern concerns such as PFAS/PFOS and microplastics — as well as chlorine, taste/odour, and metals.

The difference here isn’t whether either jug “works” (both improve tap water experience), but how wide the filtration targets are and how they’re validated and communicated.

Materials: what your water actually touches

For a product used multiple times a day, water-contact materials matter.

Phox V2 combines a glass jug with BPA- and phthalate-free plastic components (lid, handle, and internal parts). These are common in kitchenware and designed to meet food-contact safety standards.

Duryn One is designed with a plastic-free water path. Filtered water only comes into contact with:

• High borosilicate glass

• Stainless steel

• Food-grade silicone seals

Even the filter end caps are stainless steel — a deliberate materials-first design choice.

Capacity, refills, and daily use

Phox’s smaller capacity can suit individuals or couples who don’t mind more frequent top-ups and like the granule refill approach.

Duryn uses a replaceable cartridge. Replace after 100 US gallons (approximately 379 litres) or 90 days of use, whichever comes first. Higher usage may require an earlier replacement.

Maintenance style differs:

• Phox: refill granules more often

• Duryn: replace cartridges periodically

Certifications and testing (and what they’re designed to measure)

Phox highlights EN 17093, along with references such as NSF/ANSI-61 and WRAS approval.

Duryn highlights NSF/ANSI 42 & 372 and independent testing through IAPMO, focusing on chlorine reduction, material safety, and lead-free compliance — while also positioning testing around a broader contaminant set.

Which one makes sense for you?

Choose Phox V2 if you prefer a refill-based system, value reduced waste, and want clearly defined reductions focused on taste plus certain metals.

Choose Duryn One if you prioritise a plastic-free jug, broader filtration targets (including modern contaminants), and a larger jug designed for higher daily water intake.
Duryn replaces gravity filters itself and not just jugs. 

Detailed comparison (Phox V2 vs Duryn One)

Editor’s verdict: Phox V2 and Duryn One both make a meaningful upgrade to everyday tap water, but they’re built for different priorities. Phox is best viewed as a refillable, granule-based jug with performance framed around a more limited set of defined reductions (such as chlorine, taste/odour and certain metals), and it will appeal to anyone who enjoys the flexibility of swapping refill blends. Duryn One, by contrast, feels like the more complete choice for most UK households: it’s a zero-plastic design built from borosilicate glass, stainless steel and food-grade silicone, it offers a larger capacity for daily use, and it’s engineered around broader modern filtration targets — including PFAS/PFOS, microplastics and pharmaceutical residues — rather than a narrower list. If you mainly want a refill routine and a smaller scope, Phox is a sensible option; if you want a premium jug designed for long-term use with wider filtration ambitions and no plastic, Duryn edges it.