Cheap ways to boost Mg?

[sharuq1]

I haven't got a calcium reactor. Up until a month or so ago my Calcium levels were just fine doing water changes, but lately they have been slipping and I have not been able to get anything but precipitate in my wc water using suppliments, so my best guess is that I need more Mg (I know, buy a test kit first, I will, ) I think I will try out this Mg you guys are talking about and order some in soon as I have some spare cash. Anyone interested in doing a group order? I'm in Red Deer.