Getting Ready to Deploy... A Few Questions

[T.G]

If you can't get distilled water, use reverse osmosis purified (bottled) water.

You might also be able to talk to a medic and get a bottle or two of "sterile water" which is just distilled water that's been packaged for medical use. You can also check with some of the mechanics and see if they have access to distilled water for topping off lead-acid batteries.