Those fish will require a heater, so either have it indoors (if you want that let me know so I can help you), or pay thousands of dollars for heat, Secondly 5 peacock bass in that pond is going to get awfully crowded, those fish will get to be 2-4 feet (depending on what type it is), third, pacus also get massive, but they are herbivores (unlike the oscar and peacock bass), fourth, the bass like to jump so you have to worry about that, fifth, I think a small turtle like that might get harassed by the fish, and sixth, you will need some very good filtration because they will produce a lot of waste, you should either A, get other fish, B get a larger pond, or C, plan to get a larger pond (because it will take a few years for them to get that big), how deep do you plan to make it, assuming you make it 3 feet deep, you'll have about 1500 gallons to work with