mchambers
Former CCA member
They are the best in the US, except maybe for you! But Regina had had C123 before she bought mine, so she's been trying for a while.I would have to agree, but those guys are pretty good at this
As far as the difficulty goes, Ian Fuller told me they've never spawned for him, and he's spawned something like 150 different Corydoras species. He told me he knew someone in Europe who had done it, and I found a report in the UK. At the Facebook Corydoras Spawning Report group (yes, there is such a thing), I found one report of 100+ eggs, but no fry (or maybe one).
I have no idea why it's so hard to get them to spawn at all, let alone successfully. (I do know the secret of my success: dumb luck.)