Hey, anytime. I raise all (almost all) of the Veija's and the Paratheraps. Once they get 5"+ it gets real easy to distinguish. That is a nice looking fish. My little guy is about 4", and he is just starting to get the color in the tail.
That on the other hand is tough. Like with most Vieja's and a lot of the Paratheraps, it can be very difficult to sex. But looking at my male and female, the male is far more colorful. So if I had to guess, I would say male.