Magnesium additive: Seachem Reef Advantage Magnesium experiences?


New member
Has anybody had any experience with this product? Are there any issues with the sulfate content?

I can't get ahold of the Dead Sea Works Mag Flake locally to DIY it, and the Kent Tech M requires 1ml per gallon of tank per day, and on my 150gal tank that would just be too expensive.

I don't want to use Epsom salts based on Randy's discussion in in the ReefKeeping Magazine article on DIY Magnesium supplements.
Randy's concerns about using Epsom salts were if you used only Epsom Salts and not mix it with magnesium chloride. You will want to keep your chloride and sulfate in balance when adding a mag. supplement.

IMHO, it will be cheaper if you buy magnesium chloride from a company online like and buy Epsom Salts from the grocery store, then purchasing the other mag. supplements from your LFS. You would then mix the two together per Randy's instructions depending on what you are using to supplement calcium with. :)

The problem I have with many of the mag. supplements from your LFS is that the ingredients nor the amounts are fully disclosed in their label. You really don't know what you are buying. :(