Water filter jugs: Do they work?

Chilling should mask the flavour of chlorinated water, but another option is buying a water filter jug. We put three jugs to the test.

Filtered water in glass

A common complaint about tap water is the taste and smell of chlorine (adding chlorine to tap water makes it safe). Chilling water and leaving it in the fridge should mask the flavour, but another option is buying a water filter jug. We put three jugs to the filter test.

How they work

Brita Marella Water Filter, Prestige Tulip Filter Jug and AlkaJug by Ionza all claim to reduce or remove chlorine and heavy metals, leaving you with better-tasting water. The AlkaJug also claims to turn ordinary tap water into alkaline water with a pH of 8.5-9.5 (tap water has a pH of about 7).

Essentially, these jugs work in the same fashion:

  • All three have a disposable carbon filter.
  • Carbon is porous so the surface area attracts and holds the chlorine.
  • Heavy metals (such as lead and copper) are removed by an ion-exchange system that attracts positively charged metals.

They don’t claim to remove bacteria, so should only be used on treated water.

Test results

We sent the jugs to an independent lab to see how much chlorine and heavy metal (cadmium, chromium, copper, lead, nickel and zinc) they removed. We also checked whether the AlkaJug increased water’s pH.

  • The Brita did the best job. It removed more than 94% of chlorine and 98% of heavy metals.
  • The Prestige was very good at filtering – it removed 84% of chlorine and 80% of heavy metals.
  • The AlkaJug wasn’t as good – it still reduced levels but only by approximately 50%.
The AlkaJug succeeded in raising the pH level of the tap water we tested.

The AlkaJug did meet its alkaline claim. The tap water we tested increased from a pH of 7 to 9.7 after it was filtered.

All the jugs in our test require replacement cartridges – the filter life lasts from 150L (Brita) to 300L (AlkaJug), so this is an ongoing expense. Old cartridges can harbour bacteria because each time the filter is used some water remains in the carbon, along with any remaining bacteria. Eventually they emerge in the water from your filter.

Do you need one?

The jugs in our test did reduce chlorine and heavy metals. But a free alternative is filling a jug with tap water and putting it in the fridge. Some of the chlorine will dissipate and the chilling is often enough to mask any remaining flavour. A squeeze of lemon juice also helps.

Most of us don’t need to reduce heavy metals in our water. The Ministry of Health’s (MoH) latest report on drinking water shows 97% of monitored supplies met chemical standards. If you’re concerned about your water, you can check the MoH report at health.govt.nz. Most taps contain heavy metals, which can leach into drinking water. The MoH recommends flushing about 500ml from the cold tap before water is used for drinking, cooking or brushing your teeth.

Types of filters

If you live rurally or have your own private water supply, you may need more than a jug filter. Animal waste and fertilisers may contaminate groundwater, and water collected from your roof can be contaminated by birds or animals.

  • Tap-mounted filters sit inside the tap head, so are easy to replace. However, they slow the flow of water and don’t fit all taps.
  • Counter-top filters can handle lots of water without modifications to your plumbing. They’re less prone to clogging than jug or tap-mounted filters. But they’re more expensive and can’t be used on all taps.
  • Under-sink filters can filter lots of water at a time without taking up bench space or slowing water flow. There are two main types – one filters water to the main cold tap, the other filters to a separate water filter tap installed into the bench. Both take up under-sink space and you may need a plumber or water filter company to install.
  • Whole-house filters filter all the water coming into the house and may cost thousands of dollars to install. They’re generally only justified if your water supply is especially “hard”. This means the water has high mineral levels, which can cause build-up of scale deposits in plumbing and water-using appliances.

Buying tips

  • Check the labels and make sure it’s designed to remove the contaminants that may be in your water supply. It also pays to check the price of refill cartridges – the ongoing cost can add up.
  • Check it’s been tested and certified. NSF International provides a range of certifications. NSF42 covers aesthetic effects, and NSF53 covers health effects. The Australian New Zealand standard AS/NZS 4348:1995 sets out requirements for domestic water treatment appliances.

Product profiles

Brita Fill & Enjoy Marella Water Filter 2.4L
Brita Fill & Enjoy Marella Water Filter 2.4L
Price: $29, $32 for 3 cartridges
Filter life: Up to 150L
Free chlorine removal: >94%
Heavy metal removal: 98%

Prestige Tulip Filter Jug 2.4L Prestige Tulip Filter Jug 2.4L
Price: $49.99, $19.99 for 3 cartridges
Filter life: 175L
Free chlorine removal: 84%
Heavy metal removal: 80%
Availability: From Briscoes only.

AlkaJug by Ionza 3.5L
AlkaJug by Ionza 3.5L
Price: $60.40, $32 for 2 cartridges
Filter life: 300L
Free chlorine removal: 56%
Heavy metal removal: 50%

Note: Price is what we paid for each jug.

Whole-of-house filter companies under fire

Whole-of-house filter companies under fire


Whole-of-house filter companies under fire

In October HRV was fined $440,000 after pleading guilty to making unsubstantiated claims about its whole-of-house filters and misleading claims about tap water.

HRV isn’t the only company to fall foul of the Commerce Commission. The commission has filed charges against Kiwipure Limited under the Fair Trading Act. The matter is currently before the courts and Kiwipure is defending the charges.

Member comments

Get access to comment

Anthony W.
06 Oct 2020

Do you know of any water jugs that will remove the Fluoride from the water?
I see that the "MyWaterJug"from Waters.co claims to ... but can we believe that claim? Thank you.

Marg A.
09 Mar 2019
Brita Marella 2.4L

This jug can be bought at Mega Mitre 10 for the stated price, of $29. I have bought 2 of them as gifts.

Llyvonne B.
13 Dec 2018
Alternative to the small jugs

Stefani ( at bunnings) I think are a better option to the above water jugs. They have benchtop gravity filter and I have found them very good. They use a ceramic candle filter and the water flows through, similar to the jugs, with the advantage that they hold far more water than the jugs.

Mark J.
08 Dec 2018
Your misleading statment

I must have a better sense of taste and smell than you because I can taste (smell is slightly less) the chlorine in water that has been placed in the fridge. I tried a number of non scientific tests including leaving tap water in a bowl in the sun for up to two days and refrigerating it after different times. Aerating water reduces the amount of gas, but does not remove the salts. Which leave a taste

Maggie L.
29 Jun 2019
Chlorine doesn't have "salts"

Chlorine doesn't have a "salt" and after two days at room temp the water won't have any free chlorine in it.

I think perhaps you're experiencing a bit of cognitive priming. You expect the water to taste different so your brain gives taste reception higher priority causing you to notice differences in flavour that were probably already there but you hadn't noticed before. It's like those pictures where it could be a vase or two faces and you can't see both until it's pointed out to you. It was always there and once you 'see' it you always see it.

Anyway, the chlorine 'smell' people talk about isn't actually chlorine but a disinfectant by-product called chloramine (this is also what gives swimming pools that chemical smell).

Chloramine is formed when chlorine (as underchloric acid) reacts with the ammonia from decaying organic waste (and urine in swimming pools). These chloramines also disinfect the water but they don't evaporate like chlorine does. Perhaps this is what you're tasting but I would expect you'd smell it more acutely as it has a strong odour.

The whole chlorine process is really quite interesting. When added to water, chlorine forms underchloric acid - some of which, in turn, expires to hypochlorite ions. Because chlorine is diatomic these two forms of chlorine can bond and are measured as free chlorine in water. Free chlorine breaks apart when exposed to ultraviolet radiation from the sun, releasing the chlorine as gas into the atmosphere. Sunlight is so effective at reducing chlorine that a bright, sunny day can do so by 90 percent in just two hours.

Interestingly, it's the unstable nature and changing forms of chlorine that make it such an effective disinfectant. Depending on the pH of water, chlorine forms different ratios of neutral underchloric acid and the negatively charged hypochlorite ion. Underchloric acid is really good at penetrating the cell walls of pathogens where it comes into contact with the pathogen's enzymes. During this contact underchloric acid exchanges a hydrogen atom for a chlorine one thus causing the enzyme to malfunction and pathogen to die.

Michelle G.
08 Dec 2018
Does it affect the fluoridation level?

Are people with these jugs still getting the fluoride?

Consumer staff
10 Dec 2018
Re: Does it affect the fluoridation level?

Hi Michelle,

None of the jugs we tested claim to reduce fluoride levels so we didn’t test this.

Kind regards,

Belinda - Consumer NZ staff

Theresa C.
24 Nov 2018
Brita - price query

I'd query $29 for the Brita Marella 2.4L jug - are you sure it wasn't purchased for $39? If price stated is correct, can you let us know where from?

Consumer staff
26 Nov 2018
Re: Brita - price query

Hi Theresa,

You can buy the Brita Marella for $29 from The Warehouse: https://www.thewarehouse.co.nz/p/brita-jug-marella-2.4l-blue/R2385348.html#q=brita+marella&start=1


Natalie - Consumer NZ staff

Lorraine B.
24 Nov 2018
Replacement cartridges

I have a Brita filter jug which is fine. However it is an old model which does not have the correct size cartridges available. I bought some on line which look correct but they are just a little too small so let the water in around the sides rather than through. I had already decided to just fill the jug and not use the filters.

Karen S.
24 Nov 2018
Counter Top filters have changed

I brought one from a great NZ seller which has 2 different attachments depending on the tap. If it's an older tap there is a rubber suction type attachment that just pushes on or if newer there is a screw on attachment. Have used both with no problems.

Pieter M.
24 Nov 2018
Water filter jugs and pH

Just a question - what are the benefits of raising the pH of your drinking water?

Consumer staff
30 Nov 2018
Re: Water filter jugs and pH

Hi Pieter,

There are various health claims about alkaline water (which has a pH greater than 7). In our test of bottled water (report coming soon) some alkaline waters made claims on their websites, such as drinking high pH water can relieve or reduce premature aging, and detoxify your body.

Although there are a few studies that suggest it might be helpful for some conditions, like acid reflux, there isn’t enough evidence to support its use as a treatment for any health condition. And as far as detoxing goes, there’s no need to drink alkaline water to do this. Your body is continuously detoxing on its own (your gut and liver break down unwanted and potentially damaging compounds, which the kidneys eliminate.

Kind regards,

Natalie - Consumer NZ staff