Any fish in the 220 right now? If not, lower the water quite a bit (maybe 1/2) and place all 3 in there. I dont know how your filtration is setup, but if you were to put guppies in there for feeders they shouldnt get sucked up. They will grow very fast and then keep increasing the water in the 220. I've done this with small small Orinocensis before in my 125 and it works very well (although they are not as aggressive as Armatus).
Chris