Water tap in kitchen is the most important source of water that we use to drink and cook our daily meals thus the kitchen sink is where most household install the under sink water filter. There are plenty of under sink water filters available in the market and most of them are equipped with filtration system that claimed to be able to purify tap water. Water that processed by these under sink water filters appear to be clear and clean, safe for consumption and cooking purpose. Well, I believe most of these under sink water filters can reduce or may be remove majority of the four categories of contaminants found in tap water such as Microbial Pathogens (bacteria and parasites), Organics (volatile organic chemicals and THMs), Inorganics (arsenic, chromium, lead and mercury) and Radioactive Elements (decay of uranium in soils and rocks).
If every under sink water filter is of the equivalent specifications and able to produce the same quality of water, there is nothing to compare. The question here is, “Why these under sink water filters are being sold at different price?”. Simply the answer is, “These are different products being manufactured by different companies, hence having different specifications on the water filter cartridges used and obviously, the quality of water produced by these under sink water filters will not be the same.
Generally, most under sink water filters would have sediments filter to remove sand and large particles, another activated carbon filter to trap synthetic chemicals and other organic contaminants. However, not all these under sink water filters are made of same quality of parts and components. As for activated carbon cartridge, it can be either in granular form or porous carbon block which perform much better than the other. Some carbon cartridge have incorporated KDF-55D which is zinc and copper to make them bacteriostatic. That means that bacteria cannot grow inside the filter. Advanced features such as combination of carbon filtration’ ion exchange, and sub-micron filtration able to produce top notch quality water that no other undersink water filter can match.
It is important that a good undersink water filter is able to aquarain vs berkey stabilize the pH between 7.25 and 8.5 which is suitable to our body to operate at optimal level, able to trap or filter away TDS, iron, and rust down to .5 microns (40 times smaller than what is visible to the human eye) which the water carry when passing through the distribution piping. Unlike, reverse osmosis system and distillation, an undersink water filter that come with selective filtration is able to reduce chemical and metal contaminants while leaving in good, healthy minerals for pH balanced, great tasting water.
Since the undersink water filter uses cartridges, especially the activated carbon cartridge, to trap and capture the harmful contaminants, it would have a finite life span to ensure its best performance. Due to the cartridge needs to be replaced at six to nine months interval, you must choose the undersink water filter company that are able to send or ship you the cartridge promptly. In case you forget to replace, an added service like email reminder or auto shipping will be of great value.
In short, different undersink water filters produce different level of quality water, thus the actual types of contaminants which are being filtered, percentage of harmful chemicals being reduced and species of organic bacteria being eliminated are the direct determination of the undersink water filter performance.