HydraPak Flux+ 1.5 L Bottle and Filter

What it removes from water, and how well that is proved. 8: Clearly better than most.

0.2 µm hollow-fibre filter cap. HydraPak's fact sheet names the EPA Guide Standards and NSF P231 for bacteria and cysts: a named standard for bacteria and protozoa at 0.2 µm, which is the Protection 4 line. Its shop page gives slightly different percentages and cites HSF 42, so we use the fact sheet. No virus claim, so not 5. OutdoorGearLab's lab test (SGS Labs) found 99.9% of bacteria and protozoa removed and only 29.5% of viruses, which HydraPak does not claim.

How fast clean water comes through when it is new. Real flow drops as it clogs: see Ease of use. 4: A bit below average.

HydraPak gives "more than 1 L/min", so we band 1 L/min, which is 0.6 to 1.19. Testers measured more with a new filter: OutdoorGearLab timed 28 to 38 seconds a litre (1.6 to 2.1 L/min) and saw no change over a month of daily use. Better Trail says its two-year-old filter cap stays close to 1 L/min if soaked between uses. Banded on HydraPak's figure.

How much it adds to your pack. 7: Better than most.

143 g for the 1.5 L bottle and filter cap (HydraPak fact sheet and shop page), in the 90 to 149 band. Ultralight Outdoor Gear lists 140 g.

Filling, squeezing or pumping effort, how fast it clogs in peaty or silty water, and how easy it is to clean. 8: Clearly better than most.

OutdoorGearLab (4, 8.0 out of 10) tested this exact bottle for a month: fill, screw on, drink or squeeze, and it could not find a filter much easier unless you want hands-free gravity. Drawbacks it names: some water overflows when full, the oval top is hard to fill in shallow streams, and the filter is fixed to the cap. Filter-only sources: Better Trail (5) and Bikepacking.com (3) tested the same 42 mm filter cap on other HydraPak flasks and bags (Bikepacking.com on the Seeker+ 3 L), not this bottle, so we count only what they say about the filter itself (attaching it, flow, cleaning), never the bottle. Better Trail: very little learning curve, cleaned by soaking and swishing. Bikepacking.com: the filter needs some squeeze pressure, and it rinses clean by swishing. Better Trail says the cap cannot be backflushed, but HydraPak's fact sheet shows a backflush adapter with this bottle. Average 4 out of 5, so 8 out of 10.

Reviewers disagree on this.