What color is your coolant?
You NEVER want to mix coolant, it will ruin your engine completely.
Pink is G12 coolant, add G12 50/50 with water (also called Pentosin)
Orange is GM Dexcool, add 50/50
Green is antifreeze, add 50/50
Obviously you know to make it a 50/50 mixture but if they are not the same kind of coolant you do NOT combine them. Certain coolants mixed together cause it to coagulate and become chunky which can block coolant passage through your motor and cause it to overheat.
Boost or GTFO
2012 Volkswagen Candy White CC R-Line 6-Speed manual