I got some from premium aquatics...... I am putting it into my calc ractor..... I also have kalk + 2 for my kalk stirrer it has mag and strotinum in it.... I'll probably hold out on the dolomite if im using the kalk + 2 but i do have some regular kalk that dosnt have any other suppliments, so when i get around to using that bottle I'll add the dolomite to my reactor... good luck man