I think what they're trying to say is: use water wetter in plentitude. While it wont prevent corrosion completely, it'll keep it low.

Not to get off the subject of the rad, but speaking of corrosion it would be better to use a rubber or glue type seal on a water block than soldering(silver/tin) the two halfs together? Although the solder is minimal it's still in direct contact with the copper. Would this make a difference?

Koslov: yes, with a corrosion inhibitor, you should be ok, but you'll have to keep an eye on it, and flush the coolant ragularly (1/3/6 months???). If you look at the chart (in my first post) you'll notice that Stainless 316 is pretty far from chrome (passive). In other words, water by itself will create a highly corrosive environment. If the materials touch each other (aka solder) but not through water, there won't be any corrosion, except from the ambient moisture.

Like airspirit said, use WW in the prescribed "1 oz per gallon" dilution ratio.

What about using deionized water? This rad was actually designed for it... would a copper WB hold up under deion-ed water?

Koslov: click here to go to Brian's article: "The chemicals of OC'n and Super Cooling - Coolants".

In short, WW and deionized water.

Why bother using deionized water when it's just going to absorb metal ions until it becomes something similar to distilled water?

Better to use distilled water.

Alchemy

Ah yes, that was the recommendation: distilled water, with the right proportion of WW.