Depends on what Cories you have. What are the dimensions of your tank?
Rams do better in a pair rather than a group. If you want a group then the majority of Apistogramma's are hareem species so you could get away with 2 females to 1 male. Although they are usually more aggressive and territorial than Rams, so bare that in mind.
Have you any other fish at all in the tank? If not then i would recommend some shoaling species such as Harlequin Rasbora's or some of the smaller Tetra's.