One of the most important ways to determine sex in any Herichthys, is seeing the dorsal fin.
If it has a black blotch it is often a female, males usually don't (as long as they are not hybrids, or spawning).
Both of your photos leave out that possibility, In the first the dorsal in down, and the 2nd the dorsal fin is obscured by shadows and the blue tint, obscures it even more.
Here is a female carpintus, note the obvious black color

Now a male

another way is noting the forehead profile.
A steep profile usually indicates male, females are more torpedo shaped, compare shape of the two above .
If you could post pics without the blue tint, with fins erect and not shadowed it would be much more obvious.
The head profile of yours looks male, but a clear dorsal fin shot could be the determining factor.