a regular client of mine has bio sculpture overlays. On her last visit i soaked off and applied a new set. On her thumb nail she had a brown stain mark, i carefully buffed nail and applied sanitiser as normal but still left a slight stain, anyway i thought this could not be a bacterial infection so i applied gel and rebooked to see her in three weeks. I am now wondering could this have been a green nail changed to brown. what do you think this could be? a bruise maybe. Has this happened to anyone else, advice would be greatly appreciated?