Water filters: do you need one?

A water filter may improve the taste or smell of your tap water, but be aware of the problems and cost involved.
Learn more
  • Updated:19 Oct 2008

06.Water filter profiles

The basic pros and cons of each type of filtering system are included below, as well as a rough estimate of initial costs. Ongoing costs can be determined by checking the volume or time it claims to filter before requiring replacement.

Be sure to factor in the cost of replacement filter cartridges and always replace as instructed, as spent cartridges can themselves harbour microorganisms. What each cartridge can filter varies even within the different types of dispensers.

Jug filter

jug filterPrices: $20 - $75 initial

  • Pros: Convenient, small, and easy to use and replace filters.
  • Cons: Some are slow, prone to clogging and have short filter lives, meaning higher ongoing costs. 




Tap mounted

Tap mounted filterPrices: $25 - $75 initial

  • Pros: Most convenient at tap filter, small, and easy to use and replace filters. Easily swap between filtered and non-filtered water.
  • Cons: Slows the flow of water and cannot be used on all taps.



Counter-top filterPrices: $60 - $350 initial

  • Pros: Filters large amounts of water without plumbing modification. Less likely to clog than jug- or tap-mounted filters.
  • Cons: Clutters countertops and cannot be used on all taps.




Under-sink filterPrices: $180 - $600 initial

  • Pros: Filters large amounts of water without cluttering up countertop, or attaching to existing tap. Less likely to clog than jug- or tap-mounted filters.
  • Cons: Takes up under-sink space and requires plumbing modification. Most expensive option.


Other options

You can also buy shower filters or ones built into fridge ice and water systems. These are generally carbon filters.

There is also a whole-house option, but they’re expensive and generally only justified in quite specific situations (for example, if you have a poor-quality water supply).

Filter mediums

All the filter systems above can have different types or combinations of filter mediums. Your choice depends on what you want to filter out.

  • Filtration/Adsorption Filtration involves using a substance, typically carbon, to make contaminants adhere to the many pores (like pumice) within the carbon source, also called adsorption. The source of carbon can be coconut, charcoal, ceramic, etc. This helps remove odour, taste and particles in the water.
  • Softeners If you have a hard water source, you will notice a build up in kettles, bathtubs and sinks. These are normally a result of large amounts of minerals in your water. A softener medium will reduce the amount of minerals.
  • UV Treatment This uses ultraviolet light to disinfect water, however it only works on relatively clear water, otherwise the light doesn’t penetrate sufficiently.
  • Reverse-Osmosis This passes water under high pressure through a thin membrane. Most contaminants are physically blocked and washed away. It uses a lot of energy and water; up to 85% of the water can be wasted in the process. However, it does remove a wide range of contaminants.
  • Distillation This is also energy-intensive. It boils the water, collecting the condensing water to remove many contaminants, though not all.

Illustrations by Cynthia Nge


Sign up to our free

Receive FREE email updates of our latest tests, consumer news and CHOICE marketing promotions.