[timonoko]

Bloody Hell I did not know that. I have parts of broken Katadyn PUR-06. I was thinking of rebuilding it from better materials. The pressure recovery is the worst part. I can totally fathom now a hand-held desalinator with only rotating parts running from solar or Li-On batteries.

[timonoko]

PUR-06 lasts 300 days, not "indefinitely": https://youtu.be/dNjdgfGgPdE?t=208

[pfdietz]

I don't know how well this would scale down. Viscosity would work against you.