Since your are feeding flake food, I am fearful that you cory cat may not be getting much to eat since the flake floats at the top and they are generally bottom feeders. You may want to get some shrimp pellets or some food specifically made for cories so he can have a pellet a few times a day as they are true foragers and need to have some food at the floor of the tank to hunt out to keep them active and fed.

I would put a pellet or two down for him 3 or so times a day to keep him happy and healthy . Otherwise the advice you hve gotten is fine.

Rose