Angelfish Colours

I have had a black and white angelfish for just on 2 years now, The other day I thought he had whitespot but on closer inspection the white on his top fin and lower fins had a nice light blue colour streak through it.

Would this be a mating thing or is it common. It hasn't happened till now

Adult colors............Frank

There was a time not too long ago when the only angelfish available for aquariums were silvers, that is they had a silver body with clearly defined black stripes. Now angelfish come in almost all black, almost all silver, with orange or gold patches, with blue highlights, with reflective scales, and with marbling of various degrees. There are also fin size variations. By the time their bodies are pea sized, you can usually tell what their adult colors will be. Depending on the variety of angelfish, their colors may become more intense during the spawn cycle. If you notice a sudden change in basic coloration, watch for fighting, diseases or parasites.