use decon 90, CIP 100 or Glass-Klenz all of these clean glass fantastically, unfortunatly you would need some one probably at a lab or food/pharmaceutical manufacturing facility to get hold of it.
failing that simple detergeant washed off with some water with added vinegar, use the Acetic acid in the vinegar to stop any calcium in the water from leaving any deposits. Which is very commen in hard water areas.
Note: Vinegar is very good at getting rid of limescale in your ketle. Add it and boil ensuring you rinse very, very thouroughly before using it. please not clear vinegar is best not some psh Balsamic
