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Two filters are compared at this stage: the Katadyn Hiker and the General Ecology First Need. Both are filters, but the First Need is also a purifier. The Hiker is my personal unit and was obtained (long ago) from a bushwalking shop; the First Need was lent for the trial by the importers Purifiers (Australia) Pty Ltd. Pricing is not quoted for either unit: it changes, and frankly I do not think the price matters on this one item. They are very roughly similar in price: what matters far far more is whether you get sick.
The Hiker has been used for many years by the author. The First Need (FN) was tested by the author for a limited period of time. It has not been tested for capacity, nor for operating force at the end of life. A brief comparison of the specifications for the two follows:
| Item | Hiker | First Need | Comments |
|---|---|---|---|
| Weight (gm) | 315 | 425 | Empty of water! |
| Size mm*mm | 165*60 | 150*130 | Not counting hoses etc |
| Capacity (l) | 800 | 600 | Quoted, not tested |
| Flow Rate l/min | 1 | 1.8 | When clean |
| Force (est) | Low | Low | When clean |
| Filter pore um | 0.3 | 0.4 | |
| Core | Activated carbon | Electrostatic filter | |
| Protozoa | Stopped | Stopped | EPA certified |
| Bacteria | Stopped | Stopped | EPA certified |
| Viruses | Not stopped | Stopped | EPA certified (FN) |
| Chemicals | Stopped | Stopped | Claim |
| Prefilter/float | Sponge | Micro-mesh | |
| Input hose | Yes | Yes | |
| Output | Hose | Screw to bottle | |
| Field service | Yes | Yes | Tested |
| Rest on ground | Yes | No |
So the big differences are as follows.
On the other hand, they share a lot of common ground:
The author has tried many filters over the years. They all clog up, but the Hiker has an enormous surface area compared with the rest, and a far greater life to match. In fact, I have used my Hiker for so long the pump shaft is starting to show some minor wear. In addition, from conversations with other walkers in Australia and overseas, and from news groups and so on, it is clear that the Hiker is the most common unit in the field.
The First Need is based on a filter technology different from the rest: the Structured Matrix. This has small pores very much like all the others. It has some general chemical absorption materials like the others (unspecified, but very often activated carbon). The extra is the "electrokinetic attraction" surfaces which grab all the very fine particles. I say "all" because several of the independant test reports they supplied did state that zero levels of all bugs were found in the output. It is also interesting that General Ecology claim to supply their filters to Qantas, JAL and many other airlines.
Which is the better one? That will depend on where you are going and what sort of water bottles you use. If you are going overseas to a country like Nepal, the First Need would be an excellent choice. To use the Hiker for the same trip you would need to add some chemical to handle the (many) viruses. On the other hand, if you use a PET bottle (which does not connect with the First Need at all,) the Hiker is more convenient. The First Need is slightly heavier, but the difference is not large.
© Roger Caffin 1/3/2002