This is a discussion on Are these Dwarf Cory Cat? within the Freshwater and Tropical Fish forums, part of the Freshwater Fish and Aquariums category; -->
Byron the four of them seem to stay together most of the time or at least in twos although I have seen them also ...
Byron the four of them seem to stay together most of the time or at least in twos although I have seen them also sometimes swimming with the group of Ember Tetras. When they are in groups of 2 its always one of each kind. So I think if you don't think it will be to much I will add 5 more to the group.
If it were me, and with a 10g and the other fish/shrimp mentioned, I would get another 3 of each, making a total of five of each species.
I've had both species in my 90g for the last year, and they always stay with their own species. I have never noticed the two mixing when shoaling, though in fewer numbers (I have 9-10 of each) that is more likely. Anyway, you have the room, and they will be more comfortable in a larger group of each species.