Different water purification materials will produce different purification effects , and consumers can choose a suitable water purifier according to their desired purification effect . , Let's analyze the advantages and effects of three types of water purifier filters commonly found on the market . The first type of water purifier filter : The water purifier using PP cotton can only perform primary filtration to filter sediment and rust , which are macroscopic particles that are visible to the naked eye . Can not solve the actual problem , bacteria and viruses this does not play any role , if not timely change , may produce secondary pollution , gain more than gain , there is pp cotton water purifier , we must often replace the pp cotton . This water purifier is cheaper than other water purifiers . The second type of cartridge filter housing : Activated carbon water purifier are better than PP cotton . Because there are many channels inside the activated carbon , its adsorption capacity is particularly strong . It can not only filter sand , rust , and other macroscopic particles that are visible to the naked eye . It can also filter impurities such as tiny solid particles and odor , chlorine , heavy metals and other harmful substances . The purified water can only become purified water , but not a good quality softened water . The third type of water purifier filter : Water purifier RO membrane is a relatively high-quality filter on the market today , which is better than the above two functions . The membrane has a pore size of 0.0001 μms , removes all impurities other than water molecules except 99.0% of the water , and the water is purified water , which solves the treatment of highly polluted water and high-hardness water . The water purifier RO membrane relies on the pressure exerted by the machine on the raw water to allow water molecules in the source water to pass through the RO membrane . In addition , all harmful substances such as fine impurities , excessive inorganic salts , organic matter , heavy metal ions , bacteria , viruses , pesticides , and chloroform wastes in raw water are trapped , and these harmful foreign substances and salt are discharged through the continuous discharge of concentrated water . , Is a very clean drinking water . From the comparison of the above three water purifier filters , the effect of the RO membrane is excellent .