I have multiple pairs of breeding convicts. The pairs that are successful, the male is overwhelmingly larger and is dominate. They spawn and raise the fry.
I have 1 pair in which the female is larger and more dominant. They spawn, as convicts do, eggs hatch and they'll raise them for ~10 days until 1 day I notice all the fry missing. This has happened at least 10x. The pair with the dominant female will canabalize their fry. This very same female had previously paired and spawned with a larger, dominant male and successfully raised fry.
I figured it must be this particular female eating her young without a dominant male around to protect them, so I paired that female with a larger, more dominant male (all my dominant males have huge nuchal humps). This resulted in fry which were successfully raised by the parents.