Verified answer

If your convicts have paired off then let them be. Don't bother with anything because the pair once they've spawned are amazingly good parents. They lay eggs, so they aren't technically pregnant like live bearing fish. They will do their best to protect the fry for as long as possible. You will probably need to feed them some form of fry food, be it baby brine shrimp, golden pearls, or the like. But the parents are very good guardians and will stand down most other much larger fish in protecting their brood.