Check this page and see if you think it might what you are seeing:
<http://www.turtlepu ddle.org/ health/shellrot. html
Mary at the TurtlePuddle
Michael Myers wrote:
> Hi gang,
> Tonight I was cleaning my mud and musk turtles' aquarium, and noticed
> the musk seems to be developing a little pit on one of his carapace
> scutes. I have never encountered this before, but this guy seems to
> have had shell issues since the get go.
> Since I haven't had this issue before, I don't know how to treat it.
> The mud turtle's shell is perfectly fine, the water temperature is
> usually between 75-80 degrees, the water is filtered, and the
> appetites are intact. Does anybody have an idea why this might have
> started, and how to prevent the pit from becoming any bigger, and heal
> the current spot?
> One thing I have noticed that I've wanted to mention here is that
> after changing the water, a few days later an oily film will form on
> the top of the water. Anybody encounter that before? I use the Fluval
> 2 plus to filter the water, but this seems to form in all my
> Any help would be greatly appreciated. Many thanks in advance.