Posted: Mon Jan 12, 2015 12:04 am Re: My turtle stopped eating, I'm worried
Interesting. I've only seen that color of poop once--with my musk turtle. As it turned out, she ate a piece of toilet paper. I know this is a long shot, but is there any chance, even remotely, that your turtle ate something it shouldn't have? Were you wiping off any surfaces with a paper towel? If so, that would explain the lack of eating and light poop.
Something you might want to check is the inside of his mouth, next time he opens it all the way. Some turtles get mouth rot (stomatitis), and that impairs eating ability. I'm not saying he has it, just a possibility.
I also just saw what you said about the lack of basking--assuming that your water is still 28C and you still lack a 30C basking spot (which, by the way, should actually be around 32C), your turtle is not being thermally motivated to bask. As long as your water is warmer than your land area(s), it won't bask because its cold bloodedness won't let it! Another possible factor is your bulb. Is it a tube, or a compact fluorescent? The compacts have been known to cause eye damage and may put out unpleasing light patterns to the reptilian eye.