I'm sure many of you do this already and I'm actually mad at myself for not discovering this sooner as it would have saved a lot of time and effort in the past! I used a mr clean magic eraser to clean the glass on my tank today because I was too lazy to walk upstairs and get the usual micro fiber rag for cleaning the outside of my tanks with. To my amazement it cleaned the glass to a sparkling look ! I then decided to use a new one for the inside and it cleaned the algae off with no effort at all!
I then decided to clean the glass lids that had developed hard water residue on , now it did not take it all off but it did clean the glass again to a sparkly finish where you can barely see the water residue. I'm sure if I had time to soak the glass in vinegar and then try with the magic eraser, it would eventually come off ! Anyway I hope if you are not already using this product , you will give it a try .
+1 for stevenjohn21's suggestion. I was out on Sunday and picked up Mr. Clean Magic Eraser Original and tried them on a tank that had some stubborn GSA/GDA. It worked great, much easier than most algae pads. Then I tried in on my 20+ yo Versa-top. It did well on the typical water spots but I still had to use a single edge razor blade scraper to remove the stubborn calcium deposits.