Brita Marella Cool filter jug

The Brita Marella Cool water filter jug promises "if you can't taste the improvement - your money back".

We put it to the test by carrying out a "blind" taste comparison with Wellington tap water, and three staff members also tried it out at home (each using a different water supply).

How does it work?

The working part of any filter is the cartridge. The jug's Maxtra 4-stage cartridge has an initial mesh filter to remove particles from water, an ion-exchange filter to remove heavy metals such as lead and copper, an activated carbon filter to reduce off-tastes such as chlorine and chlorine by-products, and another mesh filter.

Brita has shown us test evidence that the cartridge will do what it claims.

You need to change the cartridge regularly as the filter's effectiveness declines with use. In the lid of the jug there's an exchange indicator to remind you to get a new cartridge every eight weeks.

The jug won't remove fluoride, nor does it claim to. And it doesn't remove disease-causing organisms such as bacteria, giardia and cryptosporidium.

Better tasting water?

Three staff members compared the jug's filtered water with their local water supplies in Featherston, Otaki and Waikanae. All thought the filtered water tasted better, and two said they'd be likely to buy the jug; the third thought Featherston tap water was OK anyway.

The 13 staff members who compared the water with Wellington tap water all noticed a difference and all except two preferred the filtered water.

Our verdict

The Brita Marella Cool jug improved the taste of our tap water - and it's a lot cheaper than buying bottled water. The jug costs $35 to $40 and replacement Maxtra filters cost $14. That's a running cost of $1.75 per week.

Also ... a warning

Remember the Brita Marella Cool jug's filter doesn't remove disease-causing organisms. So only use the jug if your tap water has already been treated to make it safe.