Sorry to take so long to answer. (You can always email me) I really don't get on the board too often (just because my eyes hurt too much) and I was lucky I saw your posting.
I started out taking the Magnesium Orotate from Candida Wellness Center (800-869-1613) (mail order). 2 caps have 80 mg of Magnesium Orotate and 30 mg of Potassium. It was recommended I take 12-15 caps a day. One bottle of 90 caps costs about $27 + postage. I had NO side efffects taking 12 a day (other than empty pockets).
Then I ran out and didn't want to pay that much again and bought Magnesium Asporotate by Solaray (a brand you can get at about any health food store). A bottle of 120 caps was about $13. 2 caps contain 400 mg. (I took 3 caps and had side effects) BIG difference in price and mg. amount between the 2 companies. Sometimes you get what you pay for and sometimes you don't. In this case I just don't know. The first brand could be a much better quality - but then - how does one know?
I started taking the mag. Sept. 11 (easy day to remember) and still see no change... but then these things can take a few months to help. I hate all the unknowns but I guess that's life. Good luck and let me know how YOU do!