bolivians and blues will get along. the blue needs acid ph and the bolivan could care less. same with the kribs. Male kribs tend to be mellower than females unless they are paired. if they are paired then they are all violent. Only put ONE krib in the tank. If they breed, its gonna suck. The rams wont get violent if they breed- atleast the bolivians wont. And, odds are, youll never breed the blues. So, yes, it will be just fine. Ditch a krib and youre cool.