Pure Water in a Small Package: Under-the-sink Reverse Osmosis Systems

Under-the-sink reverse osmosis filter systems are a type of residential reverse osmosis filtration system that can be installed under the kitchen sink. This is the most affordable type of reverse osmosis filter system. The package usually includes a pre-assembled reverse osmosis filter system, 3.2 gallon tank to store the reverse osmosis water, an additional faucet to dispense the reverse osmosis water, and a set of tubes and fittings to connect the reverse osmosis filter system to the feed water and drain lines. Reverse osmosis filter systems usually include one or two preinstalled pre-treatment filters, a reverse osmosis membrane and post-filter.

Sediment and activated carbon filters are the most common pre-treatment filters. They are required in order to protect the reverse osmosis membrane from contact with sediment particles and harmful chlorine and chloramines. A reverse osmosis filter system may have one, two, or three preinstalled filters in front of the reverse osmosis membrane. These filters fulfill the function of sediment and chlorine removal. The sediment filter will be first and carbon filter(s) will come after that. A well-used osmosis filter needs to be cleaned on a regular basis to ensure the system’s continued efficiency.

They are two different types of carbon filters used in reverse osmosis filter systems: granulated activated carbon and pressed powder carbon block. Sometimes only a carbon block is used as a pre-filter in a reverse osmosis filter system.

Sediment filters have greater dirt holding capacity than carbon blocks. The rating of particle filtration in sediment filters varies from 1 to 50 micron. Reverse osmosis filter systems may be equipped with 1, 5, 10, 20, 25 or 50 micron sediment filters. After the sediment filter, each reverse osmosis filter system will have one carbon block or one granulated activated carbon and one carbon block filter.

After the reverse osmosis membrane each reverse osmosis filter system should have a post filter. The purpose of the last filter is to balance the pH of the water and improve the taste. An effective reverse osmosis filtration system can ensure that your water is safe to drink and has a pleasant taste.