Using Epsom salt as Magnesium Sulfate?
 

Has anyone tried to use the Epsom salt from walmart and mix it with Magnesium Chloride to raise magnesium.

LFS sells Magnesium Sulfate for $26.55 (3200g) and epsom salt is $8.76(4000g).

Are concentration the same or pureness the same? Why the price difference so big?

I've been using Epson Salts from Costco for over 5 years. I mix it with Magnesium Chloride road salt for a more balanced product. The price difference will be due to grade, markup, branding, volume, packaging, source... the usual things that make everything in this hobby more expensive than those sold as regular household products.

^^ So true. I also use bulk salts, and also mix Magnesiums too for the more balanced product. The savings are INCREDIBLE! Same goes for Calcium and Alkalinity.

To get the exact ratio in NSW it's something like 9:1 mag chloride to mag sulfate. A lot of people just use mag chloride for that reason, but epsom salt is pretty cheap so I always add it.

I have been using Fauna Marin Mg chloride and Walmart Epsom Salt for years. For 2-part dosing and balling the ratio is 5:3 chl to sulf. If you have a calcium reactor the ratio is 8.5:1 chl to sulf.

I'm using Aquaforest Components 1+2+3+ now though. :)

Thanks guys.
More questions, how does the grade affect and how do you know the grade?

also where to get Magnesium Chloride(that can be used for reef tanks) locally other than LFS?

You can use driveway de-icer but I've typically bought stuff for the aquarium trade because it's not very expensive and probably more tightly controlled (or maybe not, lol). I bought this recently;

https://www.amazon.ca/Aquaforest-590...rest+magnesium

For me it will last probably a year or more, for pretty darn cheap. If you need more they also make a 4 liter version, and JL also has their own branded stuff (ReefCrest)