Not to overdo the Magnesium. Same goes about potassium, water and everything else. My aim isn't to introduce scare, but to point out that when introducing single substances like magnesium sulfate we need to take into account also where we're at.
As an example, after an year of Mg replenishment with small quantities of Mg-citrate I am pretty sufficient in it. Such that a tsp of it now is able to make me sleepy and indisposed.
This link is an example of extreme reaction, we don't know how often this kid was given an Epsom enema, but it comes as a word of caution: //www.curezone.org/upload/PDF/Hypermagnesium/Fatal_Hypermagnesemia_Caused_by_an_Epsom_Salt_Enema.pdf