I am not going to say you have to use this or that, but.....if use dyes or colored fluids it will end up making a big mess. Pretty much Distilled water with some type of biocide will give you cleaner results over time. Some people do use corrosion inhibiters as a personal choice. I would not use anything with glycol in it, No kind of alcohol, No oils, or Dyes...I would make sure the PH is above 6.5 as well. Anyhow keep reading and learning its the best thing you can do.
For long term use without having frequent changing of the fluid and rinsing/cleaning out the system Distilled water/biocide with colored tubing is a much better choice. Even then you wouldn't want to let it go years without doing some maintenance checks.
I just bought a block from some guy who used colored fluid off ebay....
http://www.overclockers.com/forums/...ought-on-Ebay-(-Not-for-the-faint-of-Heart!-)
If this is what you want down the road then go ahead use the colored crap.