rams?

Something has to give. Another pair of rams might not work independent of the other fish. I have always allowed a 2 1/2 - 3 sq. ft allowance of space for each pair. That has not always worked as the tank crowds a little. If one is a grown adult pair it would be difficult to introduce a juvenile pair without deaths. If the ram pair has lived in the tank for some time without a competitive pair in the tank they will exhibit significantly more aggression--especially against juveniles. My best luck in a tank that small has been to introduce both pair at the same time.