As long as you avoid Dex-cool at all costs, and use a silicate-free formula, it does not really matter what color/type you
use AS LONG AS YOUR CHANGE INTERVAL IS 25K or less.
For boil and freeze protection, all ethylene glycol is the same--full stop, end of story.
The differences are all in the anti-corrosion additives...and the color dye. Europeans love silicates and hate phosphates,
and their engines are built with materials that reflect that. Asian engineers are the opposite.
Toyota's red and pink formulations are newer technology anti-corrosion formulas designed
for longer change intervals, especially in new engines. If you plan on going over 25k, use one of
these. Up to 25k/two years, a modern universal formula, in green or any other color, will do just fine.
As far as mixing goes, the anti-corrosion packages are all more or less antagonistic, so any mixing
should be avoided. If you were mixing, you probably didn't know what was in there or for how long,
anyway. So plan on picking a coolant and appropriate change interval in the near future, give the
system a good flush, and start over doing it right and you will be fine.
The green-red gelling issue was pretty much unique to the old-style Prestone green, and that stuff
hasn't been sold for fifteen years. So don't worry about that unless you grabbed an old bottle out of
the back of Dad's garage.
Me, I use Toyota Red and 30k change interval, but there are LOTS of valid approaches to this one.