Possible shell rot?

[maddiemccc]

Does this look like shell rot? If so , what can I put on it?

 

[wellington]

Looks more like rubbing on some hard surface to me. But you can keep him on a dry substrate and put antifungal cream on it if you think it's rot or if it starts to get worse.
@Yvonne G can confirm or not.

 

[axeman25]

View attachment 134298
Does this look like shell rot? If so , what can I put on it?

My male has had the same thing on and off since I got him last January. The size changes though, it will shrink up then get back to about the size of a nickel. I was told it was caused by rubbing (possibly while going into his water dish or when he plays king of the mountain in his full food dish) and to just keep an eye on it to make sure it doesn't get worse. Sorry, I know I'm not much help. How long has he had it and has it spread or have the spots gotten bigger? That info will probably be needed by someone who knows more than I. Good luck.

 

[ZEROPILOT]

Can you scrape it off with a fingernail? If not, it is likely only rubbing.
I had to reconfigure my wading pool for just this thing. My RF would scrape themselves up getting in and out.