The need for pure water is world-wide. In some countries, the mortality rate is very high because of diseases spread through impure water. Even city water that meets minimum standards contains impurities so small they cannot be tasted or seen with the naked eye. Yet they are still present. One way to remove these impurities is to purchase and install a countertop water filter.

A countertop water filter is often the most convenient and trouble free. Unlike filtering pitchers, the countertop water filter has instant access to pure water 24/7. There is no waiting for water to pass through the filter since the filtered IRO water is ready to be dispensed. Installation usually takes minutes and no special tools are needed. Simply remove the aerator and screw the attachment in its place. The filtering unit usually rests next to the sink, out of the way.

Water is diverted from the faucet through a series of filters and then back to the faucet. Because of the amount of time the water is in contact with the filters, a greater effectiveness in cleansing is accomplished.

Countertop water filters do not remove everything from the water. Desired minerals such as calcium, magnesium, and potassium are not filtered out. These add taste to water. But harmful chemicals such as algae by-products and other organic chemicals, chlorine, lead and a host of other contaminants are removed.

Some countertop water filters require that you change the filters every so often. This is because the filters, after removing so many impurities, can become clogged. When that happens, the filters aren't working as well. The result is impure water, which defeats the purpose of having a countertop water filter. So check the filter's documentation to see when to change the filters. Some models come with an extra change of filters but others require one to buy them so check to make sure an extra set is always on hand.

Every water filter system will have some type of on-going cost. For countertop water filters, the cost is the replacement filters. Yet, in spite of this, it is still cheaper than bottled water, and the convenience of having an endless supply of filtered water at the faucet is a strong incentive to consider purchasing such a unit for a home and family.