speakerguy

Is the MgSO4 in PPS Pro anhydrous or is it MgSO4*7H2O (the hydrated crystalline form)?

Thanks!

hoppycalif

MgSO4 is extremely hygroscopic - it absorbs water with great enthusiasm. So, I doubt that you can buy anhydrous MgSO4 except perhaps at a chemical supply place. Epsom salts is what we can buy and cheaply.

speakerguy

That's what I figured. I just wanted to double-check since it would make a significant difference in Mg concentration in the final solution.