It depends upon the pH of the water into which the salt is being introduced. Chemically speaking, salt is a base compound, falling smack in the center of the acid-alkaline spectrum. If introduced to water which has a high pH, the pH might be lowered incrementally toward the center of the pH spectrum depending on how much water there was and how much salt was introduced. If the water had a very low pH, making it very acidic, the salt would increase the pH toward the center of the spectrum.

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