[JustOneMore20]

I don't like the inch per gallon rule myself. I know if I added up the sizes of my fish in the 55g and 29g that I'd be overstocked, yet I do 50% water changes and the nitrAtes rarely go over 15ppm. So it works.

I think adding 2-4 more cories will be just fine. Its up to you fishy to add rams or apistos. Personally I think it will be fine....keep a check on the water and do weekly water changes. Everything should be fine.