Good article explaining the different types of water filters for survivalists and the different water hazards:  bacteria, virus, protozoa.  One of the main threats in Hawaii is Leptospirosis, a bacteria found in many Hawaii streams but usually not found on the mainland.  It has a 0.1micron width similar to the size of a large virus., so most filters do not filter it out.  The Lifestraw Personal (0.2 micron filter) seems to be popular but does not filter out lepto making it useless in Hawaii.

I personally use the Grayl Ultrapress and Steripen UV light, and as backups, have a small isobutane and fuel tab stove to boil water along with water purification tablets.

They test many different types of popular filters and compare them.

https://www.wideners.com/blog/water-filter-tests-for-survival/

Nice Info.
Build a Berky.
https://2ahawaii.com/index.php?topic=12053.msg115882#msg115882

I guess the type of filter you use depends on the water source.  Streams and ponds may have lepto, but water catchment, contaminated tap water, wells, etc may not and require less stringent filters.

I guess the type of filter you use depends on the water source.  Streams and ponds may have lepto, but water catchment, contaminated tap water, wells, etc may not and require less stringent filters.

For Catchment which I have lived on for 23 years,  I use a 25 micron, followed by a 5 micron, and then a UV sterilizer.
Pretty common on the BI because there is so much catchment here.
 

When I was growing up on Molokai in the 1960s, we would fill up our water canteens from the mountain streams when we went hunting.  Didn't know anything about lepto and other water borne diseases.  Never got sick from drinking that water either.

When I was growing up on Molokai in the 1960s, we would fill up our water canteens from the mountain streams when we went hunting.  Didn't know anything about lepto and other water borne diseases.  Never got sick from drinking that water either.

Water is cleaner if it's fast flowing streams and taken closer to the source.  Also a strong immune system can take care of it

The Sawyer story is intriguing.  Their mission is to sell filters so they can donate filters to countries without clean water.  The Sawyer can filter lepto.

The Sawyer story is intriguing.  Their mission is to sell filters so they can donate filters to countries without clean water.  The Sawyer can filter lepto.

Interesting.
Not many Christian references on this site.
Good one!