I'm going to post a complete history of the shell problems Spot has had and how they were eventually cured because it is such a common problem. I hope it helps turtles in the future.
For the past several years, starting long before I joined this forum, I worried about Spot's shell since it was obvious something was wrong. Until I got on this forum, it just slowly and steadily worsened. I think the problem was fungus and retained scutes caused by poor diet, inadequate lightening, never drying out, high ph and water not clean enough. It started with a few white spots on his carapace and they spread and spread. He never shed scutes.
I corrected all the habitat and diet problems and lowered the ph last year. I saw small improvements last summer and early fall when he basked outside in natural sun, then progress pretty well ceased when I brought him inside.
In January, he got a better light and I started dry docking him periodically and washing him with hibiclense and he started improving again. By improving, I mean thick layers of white shell peeled off and healthy shell was underneath. It was very very slow.
This summer, while he basked again under natural sun, most of the remaining fungus and retained scutes peeled off. But new white patches appeared that looked very much like the beginning of fungus as it had started years ago. The white patches were as visible when the shell was wet as they were when it was dry.
Spot had been living in his outside pond for around six weeks when I found that he had slightly injured his plastron. There were a half dozen small red dots on it. His basking rock was apparently too rough and the problem was exacerbated by extremely wet weather - he wasn't able to dry off for days at a time.
I took him to a good herp vet two weeks ago (JULIE CHABIRA, PRESTON ROAD ANIMAL HOSPITAL, DALLAS) and she prescribed Nolvasan soaks, Silver Sulfadiazine salve and lots of dry docking (much more than I had done in the past). Not only did the treatments cure the problems on the plastron - BUT THE SILVER SULFADIAZINE COMPLETELY - COMPLETELY - CURED THE NEW FUNGUS INFECTION ON HIS CARAPACE. Any turtle with a fungus infection on the shell should get this stuff. It's a miracle drug and it's fast.
Here's a photographic history:
January 2007
March 2007
May 2007
May 2007
June 2007 (retained scutes around margin)
June 2007 (some signs of recurring fugus infection)
August 2007 (perfect carapace - not fugus, no retained scutes)
August 2007 (perfect plastron except for remains of red dot injuries)