How to tell a male Cory catfish from. A female Cory catfish
Hi those fish are not that easy to sort. It is possible to tell males from females by comparing fish. The males have a more streamlined body then females. Females are more compressed body, and thicker at the abdomen (where the eggs are) and higher in structure.
If they are too young, it would be almost impossible. If they are older, the females generally just appear bigger than the males. As adults, the males are about 2/3 the size of the females.