I've noticed someone posted similar question to my problem and follow the advices offered on that thread. but I still find no solutions to remove the stubborn limescale from my shower screen. I've tried all the cleaning chemicals from the supermarket even used a fine sandpaper to scrub it, but still no joy.
Is it possible to remove it with industrial glass polisher like the optometrist does on glasses? Or is there professional limescale removal guys that I could call for this type of issues?