Automatic Aquarium Feeder
People come in all shapes and sizes and we all have our own character. You probably know people who are at their best first thing in the morning while others can only get things done when they are burning the mid-night oil. The feeding habits of different fish species also show variation; some (such as catfish) are nocturnal feeders while others feed during the day. Unless your own body clock is in sync with the fish in your aquarium you will not be providing them with food when they really need it. The solution described here is an automatic fish food dispenser. On the mechanical side the apparatus consists of an off-the-shelf DC mo-tor and reduction gear driving an external gear train sandwiched between two plates. It is necessary for the spacing between the plates to be greater than the thickness of the fish food pellet (see illustration). A hole in the upper plate is directly beneath a vertical tube (or magazine) which contains a stack of food pellets. The hole in the lower plate...