blue orpingtons

I am raiseing blue orpingtons and i need some advice,the first trio i had some of the chicks had red feathers come in there neck and saddle feathers after they were about 12-14 weeks old so i got rid of brood fowl and chicks.I bought new black and splash chicks that were aweek old i raised them up an bread splash to black.The chicks are realy nice great color,good laceing at 14-weeks 1 cockeral is showing some red neck,shoulder and saddle feather.Sould i be useing black and splash brood fowl that are from a b/b/s family or does that matter.My black are pure black they all are suppose to be pure.Any help will be apreciated.
thanks alot