Best Ways to Purify Water Off-Grid?

[BlueMarigold]

Finding reliable ways to purify water off-grid has become a real priority for me lately. I’ve relied mostly on boiling and a Berkey gravity filter, but I’m looking to broaden my options. There’s always talk about bleach, iodine, or even UV pens, but I wonder about the long-term sustainability of those methods when supplies run thin or batteries die. Has anyone here had good luck with solar stills or sand/gravel bio-filters over longer periods?

I've read that making a decent slow

 

[OrbitJazz21]

Solar stills work, but they’re crazy slow and yield isn’t great unless you go big. Ever try running a sand/gravel bio-filter through multiple barrels for more volume?

 

[AquaFern1028]

Slow sand filters definitely have long-term potential if you build them right and keep up with maintenance. The main thing is making sure your layers are deep enough and you let that biofilm develop at the top—it’s what actually does most of the cleaning. I’ve been running a two-barrel setup for a while, and it’s worked well for garden and even household water, as long as you pre-filter debris. Anyone else have trouble with algae build-up, or is that just a summer thing here?

 

[StarlitNavigator]

Running a sand and gravel filter through multiple barrels really does boost volume, but it takes a bit of planning to keep up the flow rate and avoid clogs. I found you’ve got to clean out the top layer every so often, especially if you’re pulling from a murky source. The biofilm needs time to rebuild, though. Do you guys have any tricks for managing flow when switching between barrels or dealing with heavy rainfall?