The actual question is. What is soft water? Hard water has two very distinct disadvantages. One. Certainly, first we need to know that mostly there’re to kinds of water types, to answer this. Soap scum is the opaque coating you see in percentage of total dissolved solids in it. This can clog plumbing pipes over time, and even corrode them. Water that is hard does not interact very well with soap. Hard water produces limescale. Considering the above said. It’s chemical composition does not allow it to dissolve all the fats associated with soap, and so soap scum is created.
Soft water is water in which the TDS was removed.
So there’s no way for TDS to pass through the ‘semi permeable’ membrane used in RO water purification, the resulting water from the RO process is soft water, water without any or very little amounts of dissolved inorganic or organic solids, as we know from the post about what’s RO. Since soap likes soft water better as long as magnesium and calcium are removed you will notice that soap now makes more bubbles, when you take a bath or wash your hands or the dishes. Eventually, it also cleans better from the skin and any other surface you use it on. With that said, soap becomes more efficient with soft water.