I have a tank with filters in the corner. since it is unsightly, I covered the section with glass with one side painted black. The filter eventually started to rub into the paint and the paint started peeling. Is there a way of painting glass to make the paint stick better ? I was thinking of using sandpaper on the glass, note that the UNPAINTED side is the one that will be seen from the front, so if i use sandpaper, will the scratches be visible from the other side ? If sandpaper is viable solution, what grade of sandpaper will i need to use ?