There are no visible differences between the male and female. Only at spawing will you be able to tell the male from the female. A female has a round "tear-drop" shaped breeding tube and a male has a cone shaped breeding tube.
As far as breeding, use a pH of 7.0 and a higher temperature of 80°F. They will lay the eggs on a vertical or diagonal surface. Assuming you have a pair, they are not difficult to breed.