Glass shower doors can be hard to get cleaned sometimes. Then throw in hard water stains and you may get the feeling they will never come clean. There are all kinds of products advertising they clean hard water stains but few really work well on glass shower doors. Here is the tip, take 4 to 5 dryer sheets. Make sure the dryer sheets have gone through the dryer at least in two loads. Then apply your shower cleaner, preferably something that works well with lime stains, such as Lime A Way. Test in the bottom right corner in a clockwise motion. Look to see if there are any scratches. There should not be any but glass surfaces can vary by material so this step is always a good idea. Then start at the top and work your way down in a clockwise motion, rinse dry and repeat as needed.