Do You Need a Water Filter?

Tap water is one of our most important basic necessities. However, the tap water provided by the municipality is worrying because it contains a lot of substances harmful to the human body. You need a water filter that will allow you to drink safe and pure water and stay away from the threat of water pollution.

The Tap Water Guidelines specify that water "should contain no harmful concentrations of chemicals or pathogenic micro-organisms, and ideally it should be aesthetically pleasing in regard to appearance, taste and odour".

Water authorities use settling, coagulation, filtering and disinfecting to ensure the safety of our drinking water, using sufficient disinfectant to stop the re-growth of microorganisms as the water travels through the pipe system to your home.

The downside of ensuring safe drinking water is the lingering taste and smell of disinfectant. If you fill up a jug with tap water and leave it to sit for a couple of hours, the disinfectant smell and taste will gradually dissipate, but many people opt for a water filter system.

When you turn on your tap, you should see clear, uncloudy water. If not, or it tastes strange, then there are ways to find out why.

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 water filter cartridges and always replace as instructed, as spent cartridges can themselves harbour micro-organisms. What each cartridge can filter varies even within the different types of dispensers.

Jug Filter(Water Pitcher Filter)

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.

Water Pitcher Filter is one of the commonly used household water filters. It is easy to use and you can place it directly on the table.

Tap Water Filter

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.

The faucet filter can be mounted on the faucet for easy installation; however, you will need to change the water filter cartridge frequently to ensure that pure water is available for long periods of time.

Counter-top

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

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.

The RO System is a common Under-sink water filter that filters almost all contaminants in the water. You can drink it directly from the filtered water.

Other Water Filter Options

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

There is also an option to fit out the entire house, but they're expensive and generally only justified in quite specific situations (for example, if you have a poor-quality water supply).

Water 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: Water Filter 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 water filter 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 percent 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.

Does Water Filter Work?

How can you be sure these water filters do what they say, without proof? One thing to look for is certification. The NSF International provides a range of certifications for products that involve initial and periodic testing:

NSF 42 covers aesthetic effects such as chlorine, taste, odour and particles.

NSF 53 covers health effects such as cysts (giardia, cryptosporidium), a range of organic chemicals (such as THM and pesticides) and heavy metals.

The Australian standard AS/NZS4348 covers a wide range of contaminants, such as taste, odour and microbiological and chemical impurities. There are also standards for water softeners (cation exchangers: (NSF 44), reverse-osmosis (NSF 58) and distillation (NSF 62) systems.