You dont.
All the normal looking offspring are considered 66% possible het albino. Basically 2 out of 3 normal looking babies are hets, the other is normal, but you cannot tell which is which so they all have a 66% chance at being hets.
The best way to deal with the 66% poss. hets is to sell the males as normals and breed the females back to a het male or albino male to prove them out as het or normal.
Its not as complicated as it sounds, good luck!!