Well my persephone adults that I raised will eat pellets like good fish. My rutilans adults that I raised know what pellets are but do not prefer to eat them. All my bigger mouthbrooders have always taken pellets quite readily (they will eat anything I stick in the tank) but the rest of my smaller species tend not to be into pellets.
I have long since given up that battle so they just get to live on frozen and live foods.
Forgot to say it is NLS small fish formula and then slightly larger pellets for the mouthbrooders.