If you are not willing to buy the distilled saline sanitized dispensers which average a 5 % saline solution, using plain water should not hurt you, but if you are going to use plain water... make sure it is distilled water, to prevent any complications due to impurities or pollutants in you drinking water. The proper saline solutions tend to be approximately 5 % saline solutions. If you are planning on using table salt NaCl - MW 58.44 g/mol, and H20 - 18.016 g/mol.
Given a gallon of distilled water = 3.7854 L = .26417 kg
Using the general chemistry % by mass formula: [mass of solute (NaCl) / mass of solution (H20 + NaCl)]*100 = 5. A little algerbra and back solving implies you need 13.7 grams of salt for a gallon of distilled water to make your 5 % solution.
I use 1/2 teaspoon pickling salt per 8 ounces of boiled, cooled water. (Pickling or kosher salt is additive free and pure. Pickling salt dissolves faster than kosher, that's why I choose it.)
One professional site I read recommended up to 1 teaspoon of salt per 8 oz. of water, but I found that burned my nose too much. Most sites recommend the 1/2 tsp. amount. I find that plain tap water burns far more than salted water.
I also must use saline sinus flushes & have for more than a year. My ENT told me to make my own saline by mixing 1 qt regular tap water with 1 teaspoon kosher salt & shake well. You do not refridgerate this. It is cheap & works as well as any saline you can buy.
Hope this helps you
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