Outdoor filter bottle: how to use it, care for it and change the filter

Day two of the hike, the bottle is empty, the next village still twelve kilometres away. A clear stream babbles alongside. With a filter bottle you simply refill – provided you know what matters.

How the bottle works

The Smarald® outdoor filter bottle contains a two-stage filter. When you drink, the water is first drawn through a hollow-fibre membrane with a 0.1 µm pore size – particles and turbidity larger than the pores are held back. Then an activated carbon capsule made from coconut shell improves taste and smell. No iodine, no chemicals, no battery.

Using it correctly

Take water that is as clear as possible and from flowing water, not from puddles or stagnant ponds.
Fill the bottle (650 ml) and screw on the lid with the filter.
Drink through the mouthpiece as with a straw – you get about 550 ml per minute.
Keep the mouthpiece clean on the way.

Cloudy water? Let it stand in a container briefly until the suspended matter settles, or pour it through a clean cloth. This protects the membrane.

What the bottle cannot do

It is intended for fresh water from lakes, rivers and streams – not for salt water and not for chemically polluted water, for example downstream of industrial sites or heavily fertilised fields.

Care and filter change

After the trip, rinse the bottle with clean water and let it dry open.
Protect the filter from frost – freezing water can damage the membrane.
Depending on water quality, the filter lasts for up to 1,500 litres. If the flow drops noticeably, it is time for the TWZ-003 replacement filter. Both filter parts are easy to replace.

The most common mistakes

Drinking from muddy puddles. A lot of dirt clogs the membrane quickly.
Leaving the filter in the car in winter. Frost can damage the membrane.
Filling it with sea water. The bottle does not filter out salt.

In short: take clear fresh water, drink through the mouthpiece, rinse and dry after the trip, protect from frost. After up to 1,500 litres – or when the flow drops – change the filter.