Most backcountry water filters rely on one of two technologies: ceramic filtration and pleated fiber filtration. Ceramic filters have a long lifespan and can be repeatedly cleaned if they become clogged, but have a slow flow rate and can be difficult to pump. Pleated fiber filters do the same job with a faster flow rate, but they can become clogged with silt and other solids and are not cleanable.
The new Katadyn Vario water filter combines the benefits of a ceramic filter with those of a pleated filter by allowing you to choose whichever filtering mode is best for the water you’re treating. When filtering dirty or silty water, the ceramic filter can be engaged, slowing the flow rate of the filter, but lengthening the effective life of the primary pleated filter.
The Vario contains three distinct filtering elements:
A ceramic disc prefilter.
A pleated glassfiber primary filter.
A replaceable carbon core.
In “longer life” mode, water passes through all three filter elements at a rate of up to 1 liter per minute. As the name implies, this mode lengthens the effective life of the pleated filter by first forcing water through the ceramic prefilter. When used in dirty water, the ceramic filter catches the worst of the contaminants. The idea is that this prefiltering will keep the pleated filter from clogging prematurely.
In “faster flow” mode, the Vario can treat up to 2 liters per minute, bypassing the ceramic prefilter and relying on the pleated filter. In areas where the water is mostly free of suspended solids, the pleated filter can work quickly without fear of clogging.
Switching between modes is straightforward: just unscrew the top of the pump to reveal the ceramic disk housing. A twist of the housing switches between “longer life” and “faster flow” – the mode names are molded into the plastic housing and the selected mode is visible through a cutout in the filter body.
In both modes, the filtered water also passes through the Vario’s carbon core, which removes chemical contaminates. All three filter elements – ceramic, pleated, and carbon – are replaceable individually, and the ceramic prefilter can be cleaned in the field.
The Vario has a couple other innovative design features, most notably a dual-piston pump design which moves water through the filter on both the up and down stokes, providing increased flow into the filter and a smooth, consistent pumping action. The piston and handle assembly breaks down easily for cleaning.
On the output end, the Vario will mate with the threads on a standard Nalgene bottle. Alternatively you can attach the hose from your hydration bladder, with or without removing the filter’s bottom cap.
One might expect all of this technology to come with a serious weight penalty. But at Katadyn’s claimed weight of 15 ounces, the Vario is an ounce lighter than the popular MSR MiniWorks EX.
Chris Voxland, Katadyn’s vice president of operations, said that the Vario is expected to have the broadest appeal of any filter in the Katadyn line, and he expects it to compete directly with the MiniWorks EX. The Vario won an ispo Outdoor Award at its European debut.
The Vario will be available in January 2007 at a suggested retail price of $80.