[QUOTENot off hand. Home Depot may even sell a suitable product in the lawn lime section (they do have dolomite there), but I've not tested any for purity. [/B][/QUOTE]
I tried the dolomite route but from what I've been told by my aquarium suppliers that they no longer bag up dolomite like they used to, and the only dolomite I could find was the Estes and they coat it with some sort of clear coat product. This thread has rekindled my search, it certainly seems like a good idea to keep Mg levels up in, especially in a big system.
I also get the Dead Sea Mg, and the packaging is the same as
"It is a white bag with a big dark blue square in the middle on botrh sides that says "magneisum chloride" in several languages".
Thanks,
Joe