greenmaji
Aquarium Advice Addict
AP makes a tapwater "purifier" that has DI fiter media in it for this purpose.. Im sorry I didnt find this post to follow up with your progress.. Im not sure what online pet stores are based in Australia, we have some members from there that might be able to help if you cant find one.. but I will post a link to what this product looks like.. HTH
http://bigalsonline.com/catalog/product.xml?product_id=22577;category_id=1755;pcid1=;pcid2=
http://bigalsonline.com/catalog/product.xml?product_id=22577;category_id=1755;pcid1=;pcid2=