Um , I'm not sure if I can post this or not but I found a Article on the properties of coolants for Liquid Cooling Computers . It breaks down and explains everything about the metals you have in a loop , what corrodes other metals , and a lot of things .
It's a long read but very informative . It can be found here:
http://www.overclockers.com/pc-water...istry-part-ii/
See what you think of it and from the article , what you would use . Distilled water is a given . Also Silver added has been suggested before as well as not to use dyes . Well give it a read and you'll see what I mean .