About the reviewer
Pemba guided trekking groups between Pokhara, Syabrubesi and the Kathmandu Valley rim for eleven seasons before he started repairing gear out of a workshop in Nkululekoport. He ran the water treatment tests behind this review: four systems, three routes, two seasons, and one December night cold enough to crack two filters left in a dormitory.
His work on this desk is narrow on purpose. He tracks how chlorine dioxide tablets behave above 3,000 metres, how long a hollow-fibre filter lasts before the flow drops, and which backup plan actually holds when a primary system fails at a lodge with no spare parts. The illness notes in this review come from his own earlier trips, where the mistake was skipping treatment on a refill rather than choosing the wrong device.
He does not accept sponsored placements, and no brand sees these notes before publication. If a filter cracked, it is written down as cracked.
Questions about a specific filter or tablet brand are welcome. Send the model and the route, and the reply will be practical rather than promotional.