Patti:

Thank you for your acetone fixation of frozen sections recipé, but if
the ionic concentration of the tap water is critical, I'd be wary of
using it outside Seattle.  This can vary enormously from one area to
another.  Years ago, detergent manufacturers had to formulate their
washing powders differently for the hardness or softness of the tapwater
in different places, and your water may be at one extreme or the other.
The trick is to try it and see if it works in your area with your
tapwater.  Maybe the "tap water" substitutes for bluing would work as an
acetone diluent?

Thanks,

Adrian Leek.