This is definitely shell rot. Just to be clear, it's best to have the rot tested. There are actually a variety of bacteria or fungi that can take part in the development and progression of shell rot.
Whether you have the time/cash to take the turtle to the vet, I'd start treating the turtle for rot. Take the turtle out of the enclosure every night, and clean the area with 5% nolvasan (chlorhexadine) solution and 95% water. Don't be scared to really get in there, and be sure to debride any dead tissue there. Then, apply silvadine to any areas that bleed due to debridement, and dry dock the turtle overnight, until the next morning. This has worked for me every single time I've dealt with shell rot, and it is the method recommended in Amanda's book.
Don't buy nolvasan. The generic version cost about 8 times less and a exactly the same. Silvadine needs to be obtained through prescription most of the time, although I think it may be available over the counter now. I think I've seen it at cvs recently. Betadine is no longer the preferred disinfectant, as it is too invasive and tends to harm healthy tissue.
This is definitely shell rot. Just to be clear, it's best to have the rot tested. There are actually a variety of bacteria or fungi that can take part in the development and progression of shell rot.
Whether you have the time/cash to take the turtle to the vet, I'd start treating the turtle for rot. Take the turtle out of the enclosure every night, and clean the area with 5% nolvasan (chlorhexadine) solution and 95% water. Don't be scared to really get in there, and be sure to debride any dead tissue there. Then, apply silvadine to any areas that bleed due to debridement, and dry dock the turtle overnight, until the next morning. This has worked for me every single time I've dealt with shell rot, and it is the method recommended in Amanda's book.
Don't buy nolvasan. The generic version cost about 8 times less and a exactly the same. Silvadine needs to be obtained through prescription most of the time, although I think it may be available over the counter now. I think I've seen it at cvs recently. Betadine is no longer the preferred disinfectant, as it is too invasive and tends to harm healthy tissue.
I wouldn't put any light on them. I put them in a container, with a small hand towel under them, so they don't sit in their wet excrement. Just make sure the area is a comfortable temperature, above 65 and below 85 degrees, where it is dark, to avoid stress. It's pretty simple.
A lot of sources say to dry dock for an hour or two. I say, go the whole night and really dry out the area. You have to treat such things aggressively and nip the issue in the bud, or it will get worse, and that's not good.
Depends on how she's basking. She'll rot is usually caused by some combination of shell abrasions and inadequate basking behavior. I personally wouldn't treat her, but I'd be watching her shell closely for signs.
She might need a good shed. Could be air trapped under the scute, but that's just a guess. Supplementing the diet with a bit of vitamin e through the introduction of wheat germ pellets might help with the shedding.