That is one of my favorite things to feed my fish. Right now its been so dry that I have no worms in the yard. (I do not use chemicals or pesticides so I feel its safe) I will probably buy some bait worms for fun.
I have been feeding Hikari Sinking Carnivore Pellets, frozen bloodworms, some squid and shrimp from a frozen seafod mix (for people) and that is it for now. I do have NLS and frozen brine shrimp which I have not tried yet.
I dont want to try larger worms just yet.... the smallest sen might get mistakenly ate, because he is about 1/2 the size of the others!