I could never find much info on this subject, So now that my puns are breeding and i have fry I will share my experiences.
In the picture above you can see the differences in color between the two fish, the one on the left is the female, showing more of a dingy yellow in the fins and skin.
The fish on the right is the male,he almost has a clear look to his body. They will start to show red in the tail and or black pelvic fins and possibly a faint egg spot at around 1 inch. Any way this is my experience with telling the male from female at a young age, thought i would share and maybe help someone else