Oxygen is an important factor for maintaing worms in a compost.The food decomposition process requires a great deal of oxygen. If oxygen levels are low, anaerobic processes will take over and cause chemical reactions and strong odors that will stress or kill your worms and make the bin unpleasant to be around. To keep oxygen high, ensure that your bin has plenty of ventilation either through air holes or porous materials. You can also leave the lid off of your bin temporarily.