To choose a good sink water filter, determine the specific contaminants in the water supply, and purchase a filtration system that is certified to reduce those contaminants. The first step is to obtain a report on the water quality in your area to identify these contaminants. It is also possible to have the water tested yourself, which is the best option for those with private well water.
Different filters are certified to reduce certain contaminants, which is why it is important to know what is in your water and what contaminants you need to reduce. Also, two filters that are certified to reduce the same contaminants may reduce them with varied effectiveness, so there may not be one product that is the best at filtering out all contaminants.
The two main types of water filtration systems are point of entry and point of use. Point-of-use systems are more cost effective and come in a variety of subtypes, such as faucet-mount filters, countertop filters and under-the-sink filters. Other than the initial cost of the system, consider maintenance costs. Faucet-mount filters are the cheapest and easiest to maintain, since you simply change the filter when the indicator tells you to do so. A poorly maintained system does not filter contaminants effectively.