A lot of whole-house water filtration systems use sodium or potassium chloride, two kinds of salt, in pellet form. As the water passes through the salt pellet tank, impurities are removed from the water, and then the water is channeled into the pipes that lead to the rest of the house and household appliances. For various reasons, you might not want salt of any kind in your water. If that is the case, here are some alternative salt-free water filtration systems and the filter types they use to purify your water.
Many of your water pitchers with filters use charcoal to filter out impurities. The charcoal is contained so that you are not consuming it. This same principle is applied to tap attachments, and under-sink filtration units. Each of these utilizes a charcoal filter of some kind to extract bad tastes and impurities from the water. Units for whole-house filtration using charcoal are difficult to come by, but there are water purification companies out there that can help if this is really something you want installed badly enough.
Osmosis is the process whereby something is filtered through thin membranes to reach a purer state on the opposite side. Whole-house and under-sink osmosis systems are available. Both types utilize an osmosis membrane to filter out very tiny particles of impurities. The filters have to be changed regularly since they catch not just the really small stuff, but larger particles as well. Your water purification technician can show you how to change the filters and where to buy them.
This system uses ultraviolet light to kill bacteria and help remove some of the bad taste that is in your water. These systems are commonly used in swimming pools, but they also come in the form of under-sink water filtration systems. The water has to pass through the ultraviolet filtration tubes a couple of times before it finally comes out of your tap, so you do have to turn on your water and wait a bit before you can get the water out. You may need to replace the ultraviolet light bulb(s) a few times a year, depending on your system.
This is another type of under-sink filtration system that ionizes your water. The ionized water is infused with fast-moving atoms that can kill slower bacterial atoms with heat. The full efficacy of this filtering method has been tested.