i advise you to read these quotes from Inchworm:
'I don't keep cichlids myself, but I've heard a number of stories about rams eating the eyes of the corys, and I have a one eyed cory that I bought out of a cichlid tank at the lfs, but I don't remember what kind they were. Perhaps it's OK so far because yours are young, but when they mature it might be a different story. '
'Corys are totally defenseless fish that like to swim in schools with the idea that there's "safety in numbers." In their natural environment the group would just swim away when they feel threatened, but they can't do this in a tank. They just have to live with the stress.'
'Let me give you an example of this in human terms. Compare this to being a small person living with a very large one who has been known to frequently get drunk, lose his temper and become violent with those around him. While he might not have behaved that way at home, just knowing he might will cause you anxiety. Over time, this fear could lead to depression, and poor health in general. While you might thrive in a different environment, if you cannot escape your home life, you will most likely never become the happy and healthy person you should be.'
'The first is that the cichlids can do physical damage to the corys. I have a little fellow that I bought from a cichlid tank in an lfs, and he is missing an eye. Fins and tails can be nipped at too.'
'The second is less obvious. Being confined with aggressive fish can cause stress to the peaceful and defenseless corys. While it might not be noticeable to you, the corys are likely to be nervous and this can cause failure to thrive and weaken their immune systems. In this state they could easily catch bacterial infections and die.'
please dont keep corys with cichlids