MgSo4 ?

[pelmato]

Hi
here my tank, about 1years old.


thing going find except a little cyano burst...im adding KNO3 for keep it about NO3 2ppm for the moment and the system is well responding.

but is my question.

i got MgSo4 from Planted Aquarium Fertilizer (been 2 years now, may bee more)
my Mg in the tank was at 900ppm and my Ca low etc...
i take a calculator: http://reef.diesyst.com/chemcalc/chemcalc.html

So, for add +100ppm of Mg in my ~12gallons i need too put 44grams of MgSo4.
after adding slowly (18hrs) my mix (RO water+ 44gr MgSo4) my Mg is now at 1170ppm !!

thats not +100ppm it is + 270ppm (not a bad thing, but way far over that i expect)
it like adding 120.9 grams insted of 44grams...

Do MgSo4 from PAF is more concentrate that the on sell in drug store ? (i don't think so)

could be insted of "epsom salt (MgSo4)" that i received "Magnesium chloride" ??
i remark that the powder that i have, is smaller then regular "drug store" epsom salt.... could be ?

Do you have a trick for identify the product ?


thanks !