The EHEIM automatic feeding device runs on batteries (included in the kit). An actively ventilated container with food ensures the supply of dry food to the aquarium without residue. The device is easily programmable and you can use it to set the time for feeding .The programming provides for the possibility of serving a double portion. By pressing a special button at any time, you can arrange a small "snack". The warning system will inform you about the need to replace the batteries. The capacity is about 100 g. New: on this model, the buttons are protected from water ingress. This model is a bestseller and is indispensable when you leave - there is no need to ask anyone to take care of your fish.