Doesn't mean it was retained sperm. You could have just missed on the odds.

A couple of years back, I had a big girl breed a lemon pastel and give me 12 normals out of 12 eggs ... no pastels ... I know it wasn't retained sperm, because she had only been with the lemon pastel in previous years.

A co-dom doesn't automatically mean half the babies will be that morph ... it's 50/50 odds per egg ... looks like you just had some bad luck.

The ball gods will be extra kind to you next year ... the year after I missed on those 12 lemons, I went 10 lessers out of 11 eggs in a clutch ... what comes around goes around.

-adam