You can turn distilled water into hard water by adding minerals like calcium and magnesium to it.
Here's a breakdown of how to do it:
Adding Minerals
The hardness of water is determined by the concentration of dissolved minerals, primarily calcium (Ca²⁺) and magnesium (Mg²⁺) ions. Distilled water has had these minerals removed, making it "soft." To reintroduce hardness, you need to add compounds containing these minerals.
Here are a few options:
- Epsom Salt (Magnesium Sulfate - MgSO₄): As mentioned in the reference, adding Epsom salt introduces magnesium ions, effectively making the water harder. A small amount goes a long way; start with a pinch per gallon of distilled water and test the water's hardness.
- Calcium Chloride (CaCl₂): This will add calcium ions to the water. Again, start with a small amount.
- Calcium Sulfate (CaSO₄) - Gypsum: Gypsum is less soluble than calcium chloride, so it will take longer to dissolve and may require stirring.
- Limestone (Calcium Carbonate - CaCO₃): While limestone is a natural source of calcium, it's not easily dissolved in pure water. Carbon dioxide (CO₂) needs to be present to convert it to soluble calcium bicarbonate (Ca(HCO₃)₂).
Simple Method using Epsom Salt
- Obtain distilled water. Make sure it is truly distilled and contains minimal dissolved solids.
- Add Epsom salt. Start with a very small amount (e.g., 1/8 teaspoon) to a gallon of distilled water.
- Stir thoroughly to dissolve the Epsom salt completely.
- Test the water hardness. The ideal amount of Epsom salt depends on your desired level of hardness.
Why does this work?
The addition of magnesium and calcium ions interferes with the action of soaps and detergents. Hard water requires more soap to form a lather, and it can leave behind a scummy residue. By adding minerals like Epsom salt (magnesium sulfate), you're replicating the properties of naturally hard water.
