Does anyone have any suggestions for keeping nails trim without having to actually clip them? I read about putting bricks in the cage to help file them as they walk over them. I also read that it really doesn't work. I thought that maybe lining the cage with very fine sand paper might work. I would still put bedding in, but leave a certain area exposed so as they run and play the nails would get filed. Any ideas on whether that could be detrimental to the pigs health? (Of course, the edges would be secured properly so that it couldn't be eaten). Appreciate your thoughts and advise.