If you try all this, i.e., rinse and re-rinse with de-ionised/distilled water, then use paper towels + hair dryers + hanging out to dry, chances are that you will still see old marks and new spots of fluid residue on the mirror surface. Yes it sucks, but at that point you should lay down your sponges and concede that a good mirror with few marks and a bit of dust is what you have, and have a look through the eyepiece to convince yourself that it does not matter.
