Maintenance of a Portable Filter. Part - 5

How to Maintain a Hiking Filter

Most of the maintenance for the filter involves rinsing its cartridge in clean water to remove fine debris. In most filter models, this is done using a method called backflushing. In pump filters, clean water is simply pumped backward, while in gravity filters, it is sufficient to lift the container with clean water above the container with dirty water. In both cases, clean water flows backward and washes away debris from the filter surface. Manufacturers recommend performing backflushing after every 5-10 liters of filtered water. Only a small amount of clean water is needed for this, usually no more than 0.5-1 liter.

For backflushing the Platypus GravityWorks filter, it is quite simple: just lift the container with clean water above the container with dirty water, and the water will flush the cartridge.

In some filter models, the cartridge needs to be removed from the housing and carefully rinsed in clean water, which is a bit less convenient, especially in field conditions. Ceramic filters are the easiest to maintain — they just need to be wiped with a coarse sponge or cloth. Finally, the most advanced filter model in the modern industry — the MSR Guardian Purifier — self-cleans during operation.

If you often encounter muddy or heavily contaminated water on your route, choose models equipped with a pre-filter. If there is no pre-filter, it is advisable to strain the contaminated water through a loose fabric.

It is important that the manufacturer of pump filters provides repair kits for them, which usually include lubricants for moving parts and replacement sealing rings.

Before long-term storage and after hiking, all filters are recommended to be disinfected and dried to prevent pathogenic microorganisms from multiplying on their surfaces. Typically, this requires passing clean water through them with a disinfectant added — details can be found in the filter's instructions.

When to Replace a Hiking Filter

To avoid counting the amount of filtered water, manufacturers devise simple ways to determine whether their filter has exhausted its resource. For example, filters like the MSR MiniWorks, MSR SweetWater, and Katadyn Pocket are equipped with a gauge — by applying it to the ceramic cartridge, you can tell if it’s time to replace it. For fiberglass and hollow fiber filters, a very weak water flow usually signals the need for replacement. If they are filtering water drop by drop, and backflushing and cleaning no longer help, it’s time for them to retire. Methods for checking the filter's resource should be included in its instructions or on the manufacturer's website. It’s best to clarify this before purchase.

The MSR MiniWorks EX comes with a red round gauge that can be used to determine the wear of the filter's ceramic cartridge.

What Hiking Filters Are Made Of. Part - 4