What colors are the pups of red staffy male and brindle staffy female?

This can be hard to predict without seeing the family tree of the parents. However, as dark colours are more dominant you are likely to have a mostly brindle litter. Depending on whether the mother has any red in her parentage will depend on whether any of the puppies are red like the father. Typcially, there will be one red puppy for every three brindle puppies - but I cannot be sure.