The best backpacking water filters will keep you healthy. Why leave your health to second rate water filters. While there are numerous water filters, there are only a few specially designed for backpacking, they are lightweight and reliable.
There are many different types of water you will come across in the backcountry. Some are crystal clear while others look like sludge. While some water will look more appealing than others, there can be hidden dangers in all water.
While you can boil water to make it safe to drink by killing bacteria, boiling is not always feasible. If you have a deadline or would like to make it to a destination by dark, you will not have time to bring the water to a boil and wait for it to cool to a temperature where it is comfortable to drink.
Then you need a water filter that can be repaired and maintained on the trail. If you filter silty or muddy water your filter element will clog hampering the flow of water and the effectiveness of the filtering.
I have used an MSR MiniWorks EX Microfilter for years and it is still going strong. I used it in Alaska for 3 weeks with no problem not to mention the numerous trips around NH and Vermont. All I had to do is clean the filter element when the water flow seemed slow.
The MSR filter comes with a filter cleaning scouring pad to remove buildup residue and a gauge for measuring the element to warn you the element is getting to the point where it should be replaced. The element also has a carbon core to remove unwanted tastes.
The element will filter out particles and bacteria as small as .2 microns. Most bacteria are in the 6 to 10 micron size.
You can also purchase a maintenance kit to rebuild your MSR water filter that comes with " O " rings, grease, valves, springs and a pre filter for the inlet tube.
The SteriPen Water Purifier is a new invention that has revolutionized water treatment. If the water you want to drink is clear, no need to filter it. Just immerse the Stripen in your water, turn it on and stir the water with your Stripen.
SteriPen uses ultraviolet light to render the bacteria and viruses harmless. The purpose of stirring the water is to make sure all the live contaminants are affected by the ultraviolet light. There is a visible blue light to indicate the Steripen is working.
The advantage to SteriPen is you get the full flavor of mountain water without the chance of picking up a contagious virus. Water filters only remove bacteria down to .2 microns. Viruses can be as small as .01 microns. So even when you use a filter you should still treat your water with chemicals such as iodine, chlorine or a SteriPen.
Steripen can be used with rechargeable batteries which can be recharged by an optional solar charger or with standard batteries. The standard batteries last longer and the solar charger takes a long time to recharger rechargeable batteries due to the fact that you are probably in the woods and shade.