Some great advice here. Things I learnt to definitely not feed them - chook pellets, dynamic lifter or chook shit (no meats either) They love aged bat guano. I haven't had any trouble with horse manure, even steaming.. If you can get a stacked worm farm, or make one, then you can encourage most worms to migrate up to compost food in the top tray, once their working tray is all castings. Then harvest the lower tray of castings as the others said, to use say a small handfull per watering can. Or, perhaps get a poly drum (with tap) and liquify the whole working tray into it. I use an old colander to catch most of the worms left when doing this. And make up your teas from the drum straight out the tap. Drum method avoids bringing pests like gnats indoors with fresh castings. Try not let the farm get to hot in summer. Also activate compost heaps with a handful of your farm worms. Best of luck.