[RWebb]

Thanks, Mike - I had it tested but don't know what sorts of tests they ran.
It was America's Tires or some such shop.

I've seen sets of color change test strips (paper??) for sale but am not sure if they do anything other than pH.

e.g.
http://www.amazon.com/Cool-Trak-311519-Coolant-Testing-Strips/dp/B000MIUJMO

Is this site reliable? Is that all I have to do?

http://www.autobytel.com/car-ownership/maintenance-repair/testing-antifreeze-104170/