The simplest water filter is a jug. These filters have been used for many years to purify drinking water.

Structure of a water filter jug

A filter jug is a transparent plastic container shaped like a jug with a lid. Inside, there is a cartridge filled with filtering material.

There are two types of lids for such filters:

• A lid with a pouring hole.

• A removable lid.

Sometimes, silicone pads are added to the bottom and handle of the jug to enhance stability and provide comfortable use.

Water is poured into a special funnel with a cartridge, passes through the filtering material, and collects in the lower part of the jug.

How does a water filter jug work?

The key element of a jug filter is the replaceable cartridge. It is a food-grade plastic housing with openings at the top and bottom. A special cone at the top helps accumulate and evenly distribute water through the filtration media.

The first component the water encounters is a polymer mesh that removes large mechanical particles.

Next, the water flows through the cartridge’s filtration media, which consists of several materials:

1. Ion-exchange resin – reduces water hardness and prevents scale formation. It contains sodium ions, which replace calcium and magnesium ions when in contact with hard water. Some ion-exchange resins can also remove small amounts of heavy metals.

2. Activated carbon – adsorbs:
   — Natural organic substances that cause water discoloration and unpleasant odors.
   — Chlorine, eliminating its sharp odor.
   — Toxic pesticides and chlorinated organic compounds, which may enter the water from industrial wastewater and chlorination processes.

3. Catalytic materials – accelerate the oxidation of certain contaminants like manganese and iron, removing the metallic taste.

To prevent biological contamination, some filters include silver ions in the filtration media.

4. Inert material at the bottom of the cartridge acts as a drainage layer to hold the filtration media in place.

Each manufacturer develops its own filtration media composition based on water quality, required performance, and lifespan.

Typically, a cartridge lasts 1–2 months, depending on the amount of filtration material, the quality of incoming water, and consumption volume.

Cartridge replacement

The replacement process consists of 5 steps:

1. Remove the lid and take out the old cartridge.
2. Rinse all filter parts under running water; dish soap can be used.
3. Soak the new cartridge for 5–10 minutes.
4. Install it in the funnel.
5. Filter and discard the first two portions of water.

After this, the water is safe to drink.

Rules for using a water filter jug

• Use only for tap water.

• Follow the recommended cartridge replacement schedule.

• Not intended for hot water (maximum temperature: 35°C).

Advantages of a water filter jug 

✔ Simple and effective water filtration.
✔ Affordable price.
✔ Easy maintenance.
✔ No need for plumbing connection (portable).

Disadvantages of a water filter jug 

✘ Does not disinfect water.
✘ Fixed water volume.
✘ Low filtration speed.
✘ Frequent cartridge replacements are required.