I have just started using this salt. So far I have done 3 10% water changes on my 190.
These are the readings I got when I measured my new change water
SG - 1.026
Temp. - 79 degrees
Mixed and heated for 48 hrs
Alk/hardness - 9.6 DKH
Calcium - 420
Mg. - 1320
Giving it the old eyeball test nothing seems to be reacting negatively in my tank in fact if anything my anemones (Sebae and RBTA) seem to be expanding larger and staying that way.