Corys usually breed in the spring when the water is low and then spring rains come washing plentiful food into their habitat,also Raising the water level with cooler water.
If you can duplicate that you should be successful.
I have tried and gotten them to spawn but the other fish have always eaten their eggs.
That sounds really interesting. I'd like to try that maybe when I get everything set up.
good luck, personaly I think cory's are very ugly but if u like them that's good for me good luck
They lay their eggs on a flat stone. Adding cooler water stimulates breeding. I think they breed best in a reverse trio--2 males and 1 female. Be sure to give them their own tank so the eggs don't get eaten. The easiest one to breed is the Bronze Cory, I think, which you can get really cheap, like anywhere. They tend to lay only small amounts of eggs, like 15 or so, I think. The fry are small and need tiny live foods (again, I think...). Hope that helps a little...be sure to do tons of research.