I agree, as long as the you only get 2 same sex, you should be good. I have a few male Tiger endler hybrids in with my 2 bolivians and the rams don't bug them. Even if you don't get them at the same time, the rams will eventually get over their shyness and swim with the other fish. I have a non-paired set of bolivians that are still "working on" pairing and they are fine. The females are very shy. I would get two males since they will color up nicely. I feed mine sinking pellets, frozen brine and a bloodworm treat at night. My male colored up nicely in about 2 weeks. I also recommend getting naturally dark gravel (small and smooth) or sand. Light substrate really washes them out (they do prefer sand since they pick at their food after it sinks). I love my bolivians... it's true what they say. They are bullet proof.