Just a word on Coolant, atleast the ones we use at work, MEG & MPG, Monoethylenglycol & Monopropylenglycol.
5% stronger coolant (to lower the freezing point) reduces the effect of the coolant with 10% (can transport less heat)
BUT BE SHURE TO NEVER MIX IT TO THIN! If it gets frozen inside the engine, it's game over...
And, coolant degrades over time, so meashure it. Take a few drops with you to the gas-station, they should have the equipment.