Nice tank I love the rimless look! You can get away with a trio or pair of most any dwarf cichlids in there, just be careful because they come from a wide range of areas and some prefer cooler waters than others. Bolovian rams tend to get a bit bigger than their cousins, german blue rams, gold rams etc. Apistos are gorgeous and there are too many kinds to recommend but I like caucatoides and agassazzi (spelling?) But TUIC has some really cool ones and discus origins has had many I had never heard of before. Microgeophagus are also a cool small cichlid but most need cooler water and different care