[singingintherain]

I have a porcelain tub and sink in the bathroom. I have tried many cleaners, but am looking for one which will not eat away at the porcelain finish.
I have tried those bathtub ring cleaners like Lysol Tub and Tile, those Scrubbing Bubble Guys for soap scum and even CLR(the worst)..but they all turn the smooth surface into a rough one as if they are eating away at the porcelain.
Is there a good safe cleaner for this which you have found?