SaniGloss finish has developed water spots

I have used nothing other than water and Dove liquid dish to clean the exterior of my Ultramax toilet, MS854114SG, which has developed water stains. Anyone else have this problem or have a remedy? Thanks.

I have also for the interior, but for the exterior I have used a mild dishwashing soap (Dove) that is acceptable according to the cleaning instructions that came with the Sanigloss supplemental page.

Not sure why, but I thought that Sanagloss was only inside the bowls of the toilets on which it is featured. Maybe that's because the info keeps talking about cleaning with every flush. But it likely doesn't make sense for just part of the finish to be Sanagloss, does it?

Yes the Sanigloss is only on the inside of the bowl.
We use Gel-Gloss to clean any stubborn stains from our china (can be used on almost anything).