I was told Peppered Corys are one of the easiest Corys to breed...
I have 4 'Julii' Cory myself... or that's what they were sold as!... I've since found out on this forum that they are actually 'Trilineatus' Corys (they have a 'marbling' effect on there heads - whereas true 'Julii' have spots on there heads and are much harder to find)... quite a common mistake... the 'Trilineatus' are actually lovely fish though...