yeah thats what ive been told that they are quite easygoing, the one at pet smart is very small so i would say it wouldnt have been fed feeders, i may be wrong but ill ask them, i dont plan to feed feeders to any of my fish trying to keep aggression minimal
That's good. The fish in your tank are small enough that it should be a piece of cake to get them on a pellet diet.
Also, I'd probably try the two leaf fish you had planned and just keep an eye on them in case you have to get rid of one. In a 125 gallon tank, there should be plenty of room for each to have their own space and it could probably work.
Also, if you choose a striped raphael catfish with the bichir, keep the two close in size. They should be fine together.