My cheap hydrometer reads out in temperature and gave some weird & inconsistent results. I may buy a new one, hopefully with density graduations. Used to have one like that - come to think of it, probably still have one on boat, but that is for battery acid! (just ordered a refractometer!)

By the way, our dealer has premix in their shop ready to top up cars that come in for service. Not sure if they get it that way or mix it themselves. One thing about premix, is that you know it was made using suitable water.

__________________
Graham
85 300D,72 350SL, 98 E320, Outback 2.5