Is it in white color around the nail if it is falling off? And is "Reptivite" some sort of liquid that provide vitamins for turtles?
Reptivite is a powder that I mix with a small amount of water and his pellets twice a week.
http://www.amazon.com/dp/B0002AQB6A/?tag=exoticpetnetw-20
I never really noticed a problem with the nails until they fell off, although it kind of looked like there was a shell of nail around his nail, if that makes sense...they sometimes fell off like they were shedding, other times broken off and bleeding.