Water Filters

Why a water filter

Access to clean drinking water is very important for the health and most places do not have it running out the tap. Generally, water has a lot of suspended particles and bacteria in it as it isn't always convenient to have the water storage tank cleaned and the pipes used to grant access are metal which over time do rust. Installing a water filter can help solve that issue and provide a household with clean drinking water. 

The more common filtration process

Most water filters use Reverse Osmosis (RO) to clean the water to a drinkable level. Experts agree that there should be at least 4 stages of cleansing starting from a sediment pre-filter which gets rid of the initial larger particles, moving on to a carbon block pre-filter which removes chlorine so the water doesn't taste weird and the chlorine also needs to be removed so it doesn't damage the RO membrane. Then comes the RO membrane where pressure forces water through the membrane, leaving behind contaminants. The 4th is a carbon block post-filter that removes any remaining odours and tastes so the water is good to drink. These filters should be changed every 6-9 months, depending on the amount of water being used in a house and what the local water is like. If the water flow is reduced that is a sign for the water filter to be cleaned. There are models that have up to 9 stages of filtration as well.

Other kinds of filters

Also available are countertop water filters based on the LifeStraw technology which uses 'ultrafiltration', this employs extremely small 0.2micron sized pores to filter water. It is unable to filter out heavy chemicals though. LifeStraw is very commonly used in post-disaster areas where drinking water is no longer available. These naturally do have a certain lifespan, defined by how many litres have been passed through the filter. The other and smallest water filter is one that fits directly onto the tap and has an activated charcoal (carbon) filter which is layered in a manner to remove sediment and chlorine. Maybe some brands make water drinkable but generally, this is more for physical purification to avoid secondary contamination.

Depending on your needs you can choose what works best for you.