Which Type of Water Filter

DID YOU KNOW Most water filter jugs do little more than improve the taste and odour of the water. You really do get what you pay for!

WHICH TYPE OF WATER FILTER?

I am often asked, “What’s the best water filter to buy?” and there is no simple answer to this question. This will depend on:

How much money you are willing to spend.
What contaminants you wish to remove. This will largely depend on your source of drinking water: tap, tank or bore/well. The ideal filtration system for each of these sources is discussed in the book Healthy Home, Healthy Family.
Whether you want a portable versus plumbed-in system. Most families who rent prefer a portable bench top system.
How much bench space you have.
Your water pressure. The more units incorporated into your water filtration system, the more pressure you will require.
Whether you want a point of use (POU) system ie one that is located at the kitchen tap or shower OR a point of entry (POE) system. Whole house systems are installed at your water meter and filter all the water coming into your home. Be mindful however that apart from their expense, these systems will not remove contaminants arising from your domestic plumbing.

TYPES OF WATER FILTERS

Reverse Osmosis Filters are the only system that will effectively remove fluoride, pesticides, petrochemicals, chlorine and its by-products, asbestos, nitrates, radium and heavy metals (lead, copper, cadmium, chromium aluminium…). However they are expensive to buy, install and maintain (they’ll need to be plumbed in) and they expend a considerable amount of waste water which will need to be diverted. Furthermore you require considerable under sink bench space. There is a concern that they leave ‘dead’ water. This can be addressed by using a special carbon filter made from bamboo which will remineralise and alkalise the water.
Carbon Filters. An economical solution for most families will be to purchase a two or three cartridge under sink plumbed-in system featuring a 1.0 micron pleated sediment pre filter along with one or two 0.5 micron activated carbon block filters. Apart from improving the taste, colour and odour of the water, they will effectively remove sediment, chlorine and its by-products (THMs), pesticides and petrochemicals. Carbon filters will only partially remove fluoride and heavy metals such as copper and lead. Their efficiency at removing contaminants will significantly decline with use as the absorption sites get used up on the cartridge. If you wish to remove heavy metals, use a carbon filter impregnated with KDF. These filters should only be used for cold water. These filters need to be replaced well before the manufacturer’s recommended use by date as the effective life of a carbon filter is difficult to establish and bacteria will grow on the filter media. To stop bacteria growing on the carbon cartridge, use a carbon filter impregnated with nano-silver. If you are renting and do not wish to invest in a plumbed-in system, portable bench top units are available. A two stage system incorporating the cartridges discussed above is recommended. However if finances are an issue, a single stage system incorporating one dual function cartridge featuring a pleated sediment pre filter and a 1 micron (or less) carbon block filter will still be of benefit but obviously not as effective as any of the systems above.
Ceramic filters are cheap, long lasting and portable filters that effectively remove bacteria, chlorine, sediment and rust. Most contain a carbon cartridge to remove organic contaminants such as pesticides and petrochemicals. However they are not effective in removing heavy metals, require weekly maintenance (scrubbing to remove the biofilm), can be slow to filter and can quickly clog up.
Ion Exchange Resin Filters effectively remove heavy metals, fluoride and nitrates and are primarily used to soften hard water. However they do not remove sediment, pesticides, microbes or chlorine from the water. Furthermore bacteria may grow on the beads and they may leak tiny resin fragments into the water supply which is why I don’t recommend them.

You are better off investing in a good water filter at the point of use (tap) than a point of entry system at your water meter as the latter will not address the contaminants present in your domestic pipes.

Suppliers:

Aquifer: www.aquifer.net.au
Safe-T-Bottle: www.safe-t-bottle.com