Hey everyone, I have an '06 R50 that I've owned for about four months. The coolant tank was about half-full of green liquid when I purchased the car, although the cap was missing. I picked up a replacement from BMW and went on my merry way. I popped the hood today and noticed that the tank is nearly empty. I picked up some BMW coolant. My concern is that if I top it up with BMW's blue stuff, it may not be compatible with whatever green fluid is already in there. Should I be worried? I'd like to avoid having to take it to the dealership to have the whole system flushed if possible. The temperature isn't running high at all, sitting right in the middle of the gauge at all times. Thanks for any help.