no idea, keep it sealed and you are fine. and besides you mix it 50/50 id imagine… i have 5 gallons… pm me and let me know what works for you.
what you use depends on nozzle size and how much you really get on it. my friend would use about 1 gallon(ran 100%) every 2 weeks, but he had a big dual nozzle setup and the car saw alot of 20-130 pulls in its time.