I am about ready to add some more fish to my 55g, but still can't decide what to add. As of now I have 6 cherry barbs and 5 gold barbs. I will be adding at least 2 more gold barbs as soon as I can find some females around here. I also will be adding a school of some type of cory cats. This fills out the bottom and middle levels pretty well, but I need some fish for the upper level of the tank. What suggestions do you guys have?