Relatively new fish keeper here, you can look at my posts to find my 155 gallon bowfront tank thread in the aquarium builds to see more details about the aquarium. Gave my 10-year-old daughter choice of which of several different groups of fish would be the "feature" fish for this large tank that came with our house. She chose rainbows. We currently have: 6 Dwarf Neon: I think they are split three and three 6 Boesemani: I think we have 2 male, two female 4 Millennium: three male, one female Note the sex identification above is still somewhat tenuous, these are all still juveniles and I am simply not good yet at telling. I also yell roll call to try to get them to line up and would not you know it, they just do not listen. 16 rainbow fish swimming around each other are certainly Energetic, at least they are in my tank. I have a quarantine tank that should be done cycling in a week or two, and it is another three to four weeks before I can add any fish to the main tank, So my thought was to try to pick something up as soon as the ammonia nitrate readings drop to zero for the quarantine tank and get the group of rainbow so I can watch them. I have already had one bout of ich in my first month with this tank, so not anxious for a repeat of that – thus the quarantine. I know the recommendation is to get two more millennium to bring their group to 6, but I easily have enough room in the tank to add another group of six. I wondered what type you would suggest? I am in Florida at that makes a difference for how easy it is to acquire different species. I would like something that added a different color or set of colors. What would you suggest for the final group of rainows?