It is because no type of water filter can give 100 per cent protection against health problems. But, there is more to it than this simple fact. There are certain myths we hold about our water filters and they need to be broken. Let us begin with a simple question.
What type of water filter are you using?
Most of us have no clue about the kind of water filters we use at home. Usually we buy whatever is the latest rage in the market (being influenced by advertisements). There are basically 2 kinds of water filter, warm and cold. Most modern water filters are cold water filters that directly take tap water and purify it to a drinkable condition.
When was the last time you cleaned your water filter?
Your water filter is like a sieve; it strains out the impurities and germs from the cold tap water that you are passing through it. If you don't clean the sieve after staining the tea, it gets dirtier every time and finally you will start getting tea with tea leaves still floating in it. It is the same way with the water filter in your home. If you are using a ceramic water filter, then you need to scratch out the layer of dirt that keeps accumulating on the filter.
When Was the last time you replaced your water filter?
Just cleaning your water filter every now and then is not enough. Sometimes your water filter has to be replaced all together. This is because most of the water filters that we use these days needs some or the other form of carbon cleaning method. In other words, carbon can absorb impurities. The water filters have layers of carbon through which the water is passed. The carbon absorbs impurities, germs, microbes etc, and stores them.
Now this cannot go for ever. There comes a time after 2 or 3 years when the carbon is totally saturated. Because we are blissfully unaware of this, we keep using the water filter ceaselessly. This water would be worse than drinking tap water because in addition to the microbes and germs, it also contains the harmful carbon sediments.
That is why we must read the instruction manuals of our water filters to know how long a filter lasts. In general you should change the filter of your water purifier every 6-12 months.