And some water.
...Be sure to lay in a supply of dehydrated water.
And some water....
Take a look at Berkey water filters. They stand alone...don’t have to be connected to anything... Better ones use use at least 2 black ceramic filters. Each will clean 3,000 gallons of water to .99999. When they start cleaning slowly, clean them with a green Scotch scouring pad and they’re good for the next 3,000 gallons. If all you have is swamp or muddy water, just pour it through a sock to take out solid particles as you pour it into the filter, and it’s good to go with the dirty water you put in. Ones that filter about 3 gallons a day are about $225 on Amazon.
Have you tried ‘I Can’t Believe It’s Not Water’?
It’s almost as good as Water Helper.