For those who use SSM for cleaning the usual additive is Lemishine. Curiosity pricked my keyboard and a search for the chemically minded revealed this. However we do not get Lemishine in Godzone [at least not off the shelf] and so we have been using powdered citric acid with great and possibly better effect. The cases simply sparkle.
What?s in Lemi Shine? ? UPDATED » Chemistry Blog
What?s in Lemi Shine? ? UPDATED » Chemistry Blog