We use oats and chicken layer non medicated for water we use water crystals and for the worms water we use carrots
http://s1187.photobucket.com/albums/z390/BillT1/bills%20bugs/
Use wheat bran and organic chicken layer feed the worms carrots only. Take what you need to feed out and gut load them overnight. If they are on top of their substrate they are thirsty and will eat each other give them more carrots. Potatoes mold faster and will smell. Keep the substrate dry.