Soft water is ideal for washing laundry compared with hard water. The reality is that soft water is not the norm. If you're fortunate enough to have soft water, then there are a few things you should keep in mind when doing laundry.
Detergents and Softeners
Fabrics washed in soft water last longer, and whites come out brighter because it lacks mineral deposits. Because soft water cleans clothing more effectively than hard water, you can use less laundry detergent. This will save you money in the long run, and is especially helpful for those with skin that becomes easily irritated after coming in contact with certain detergents.
If you use fabric softener, you will find that laundry washed with soft water requires less of it, or none at all. Start off by washing your laundry with half the amount of fabric softener you would normally use, then adjust that amount to get your desired results.
Those with hard water typically use warm or hot laundry water to get their clothing clean. This is mainly due to the fact that hard water often leaves mineral deposits and residue on clothing that is easier to rinse away with higher temperature water. When you have soft water, using warm or hot water to do your laundry is not necessary. In fact, your clothing will be thoroughly cleaned with cold water, and you will save on your energy costs. Washing in cold water also helps keep colors from bleeding and fading.
Soft water is typically water that has been treated to remove mineral deposits, except for sodium. Some people add table salt (the main ingredient of which is sodium) to their laundry to prevent color bleeding or to help get their clothing whiter, but when you have soft water, you do not need to add as much. Instead of adding the usual cup of salt to your laundry, you may be able to use as little as one-third or half a cup of salt.