The darkness you are talking about would that be the green parts? I did soak him today and used a tooth brush. The tip of his tail doesn't look like it is going to make it. I think he has too much stuck shed for too long around it.What she said ^^^^^ But If you are talking about the darkness, it's shedding you can see it down the tail and the legs. Give some good soaks and after about 5-10 minutes take a baby tooth brush and gently brush the area to help loosen the skin.
Oh I tried to snap it off and she swung around and gave me the WTH look opps guess it still had some feeling to it ...... so I just let it be and it came off on it's own.. Sorry Izzy didn't mean to hurt ya...ooooh - i LOVE coconut oil - use it for sooooo much !! My girl just lost the tip of her tail too. I kinda knew it was coming - one day it was at a 90 degree angle, so i just snapped it off, put on some neosporin and she hasnt missed a lick.