"I was fortunate enough to find a unit in a local thrift store minus the 12v power supply. I happened to have a suitable replacement lying around. It sat for months in the cabinet where I intended to install. My wife started a juicing diet and I jumped on the obvious composting material and have not regretted it one bit. When you add items, pay attention to the condition of the system. If interior material looks wet, add dry or "brown" material. Like a quick handful of rolled oats or sawdust. If it looks too dry, add a little water or a wet leftover. If it smells acidic, baking soda, if it smells rancid or trashy, add some brown and, just in case I damaged the cultures with sonething too acidic, a small handful of soil from outside. As long as it smells "earthy" like fresh mushrooms, you are in great shape. My plants have exploded from the benefits of this compost!"