Mag Active Liquid, Quick Absorption Magnesium, 8 oz, Source NaturalsSource Naturals Mag Active Dietary Supplement. Quick Absorption Magnesium Liquid. Magnesium supports the heart, bones, and muscles, and plays a part in energy generation and in the immune, endocrine and nervous systems. Source Naturals Mag Active is a purified liquid concentrate of activated ionic magnesium, in a broad spectrum of many other essential and trace minerals. Mag Active is naturally derived from the Great Salt Lake and has had 99% of the