Dow Flakes or similair cheap CA alternative

[Werbo]

I don't have the funds to buy a CA reactor and I am finding that the greatest expense for my SPS dominated frag tank has been calcium (I am using about 1 kg Seachem Reef Advantage Calcium - about $20 per month). I've been researching from Bev awesome list at the top of the Reef forum (great idea by the way) and was reading this article:

http://www.advancedaquarist.com/issu...l2004/chem.htm

My question is regarding Dow Flakes and where to purchase it as my Home Depot in Victoria does not carry it. From the article: "Last month I reported on the purity of several brands of calcium chloride, including the relatively inexpensive Dowflake 77-80% Calcium Chloride available at Home Depot for about $12 for 50 pounds."

Where can u buy DOW Flakes. Anyone in Victoria using DOW flakes? Anyone in Vancouver? What other safe Ca alternatives are there available until I can afford a CA reactor?