Question

what is the difference between gypsum and epsum

Answer 1

◆◆◆◆ Actual difference to be noted ◆◆◆◆

● Gypsum : CaSO4 (Calcium sulphate is the main constituent).
● Epsom (sometimes we say, Epsom salt) : MgSO4 (Magnesium Sulphate is the main constituent).

Answer 2

Gypsum bumps Calcium AND Sulfate.

Epsom is Magnesium AND Sulfate.

Epsom salt gives 26ppm of Mg and 103 ppm Sulfate per gram per gallon.

Gypsum gives 61ppm of Calcium and 147ppm Sulfate per gram per gallon.

You typically don't want Mg levels really high so there is a practical limit as to how much you can use.


Epsom appears to bump the sulfates with a small impact to magnesium.

Gypsum bumps the sulfates AND cal chloride, which I don't need.