Earthworms don’t just eat food directly because their mouth opening is really small. They require the help of many micro-organisms to help them breakdown the food for them. In fact these microorganisms ARE PART of their daily diet! The microbes include nematodes, protozoans, bacteria and fungi. So you don’t need to worry if the organics you feed them will give the worms enough protein to grow, they have plenty in their environment waiting for them!