Could be normal development of coloration. Some Sliders get black spots on their shell naturally. Could be normal development of coloration. Some Sliders get black spots on their shell naturally. it could just be algae or something like that. Just try scrubbing it with a toothbrush (not one anybody uses) do not use any chemicals
ATP has a full answer with suggested treatment. http://www.austinsturtlepage.com/Care/medshell.htm You should clean their shell with a toothbrush and water - nothing more - and only for a few minutes. This could be a result of lack space for drying or dirty water. Good luck
as they get older it is normal for their shells to darken and in some cases than can get black but if there shell has a crack or is not smooth than get him to avet
No, red-eared sliders are not illegal in England.
yes, mini red eared sliders do exist
Ghost Red Eared Slider Turtles will get to be the same size as normal Red Eared Slider Turtles, which is 10-12 inches.
Yes, red eared sliders eat minnows in the wild and in captivity.
never
no
no
yes they can be separated because by nature, red eared sliders are solitary creatures.
no
humans
No reason why not - although they may find the fruit a little tangy for their taste.