Originally Posted by neonlazer
This is probably a dum question(its 11pm so im tired as well lol) Are the problems with corrosion with the aluminum top partly from the chemicals in the stuff some put into the loop?...will it be less likely with just plain distilled water = me...just curious lol...
No, the problem is galvanic corrosion which is disimilar metals.
Aluminim in the GTX top and copper in the bottom as well as likely to have brass or other metals with a different anodic index from aluminum.
The problem is lessened when you use a good anticorrosion addative like antifreeze/ethelyne glycol/hydrx etc but not eliminated. But regular distilled water does not reduce galvanic corrosion, it's better to have hydrx or another ethelyne glycol anticorrosion addative in there.
Eventually the distilled water in the loop becomes contaminated with the metals and galvanic corrosion occurs. The GTX top is coated to isolate the aluminum in the top, but unfortunately small cracks, pits or imperfections in the coating, and damage to the coating by barb threads can allow contact. After it starts, it works it's way out radially from the point of entry, in this case it appears the barb threads is where it started.
I will never run aluminum in a loop.