Drip Filter Ceradyn

The Katadyn Drip Filter Ceradyn is a free-standing gravity water filter for groups of 10 or more, using three silver-impregnated ceramic elements with 0.2 micron pores. The Katadyn Drip Filter Ceradyn is effective against bacteria, protozoa, cysts and sediments, delivers about 4 litres an hour with no pump or power, and is rated for up to 150,000 litres depending on water quality.

Who it's for

Base camps, station kitchens, hunting and fishing camps, remote huts and anyone running water for a crowd day after day. Fill the top with creek or dam water, walk away, and come back to clean water in the lower container, ready at the tap. Katadyn rate it for clear and muddy water, and international relief organisations use the Drip as group equipment.

What it removes, and what it does not

The three silver-impregnated ceramic elements clean out bacteria and protozoa: Katadyn explain that these micro-organisms cannot pass through the 0.2 micron pores of the ceramic because of their size. Katadyn list it as effective against bacteria, protozoa, cysts and sediments. Viruses and dissolved chemicals are not on the Ceradyn's list. If there is any risk of viruses in the water, treat the filtered water with purification tablets or boil it as well.

Flow rate and capacity

• Output: about 4 litres an hour
• Capacity: up to 150,000 litres, depending on water quality
• Filter: three silver-impregnated Ceradyn ceramic elements, 0.2 micron
• Water container: 10 litres, outlet tap on the lower container
• Weight: 3.3 kg; diameter 250 mm
• Materials: ceramic and silicone

Four litres an hour adds up when it runs all day: top it up at breakfast and again at lunch and the group has drinking and cooking water by dinner. A red emergency plug lets the Drip keep running on two elements while you wait on a replacement.

Maintenance

When the flow drops, clean the ceramic with the supplied cleaning pad. Do not use soap or detergent. The ceramic can be cleaned many times, in camp, which keeps running costs low. Slide the measuring gauge along each element after cleaning; if it can slide over the ceramic at any point without being forced, replace that element. When setting up, or after fitting new elements, run four litres through and tip them out to clear the ceramic dust.

Looking after it

Clean the containers and elements at least once a month, keep the Drip out of direct sunlight, and if it will sit unused for more than two days, let the elements air dry completely. Replace any cracked element straight away. For transport, unscrew the elements and pack each one separately so they cannot knock together.