I cleaned my old pastel coolant out with distilled water and vinegar, you should have seen the slime I got out. Replaced it with this Opaque red and it's Amazing. 7 months in my loop now. No colour change, temperatures are great AND best of all no powder residue and no slime.
Well done sir.
I think the other guy didn't clean his system properly.
I changed out my old discoloured Red pastel coolant that had been in the system over a year with this stuff, 3 months later it looks worse than the older coolant i had replaced! the stuff i used before looked better for much longer, as for temps they are fine just dont expect it to look good for long!