Automated Fish Feeder

After the Fall semester ended both my roommate and I headed home for the usual holiday festivities. Our 4 fish in their 10-gallon tank had to get fed at least twice a day. Option one: break the tank down and bring them home for a total of up to 3 weeks. Option two: time-release food pellets. Option three: automated feeder. I decided to take option 3 and try to throw something together that utilized a programmable electronic timer switch that I had on hand from a previous project.

Materials Used:
- empty Vitamin Water bottle
- wire coat hanger
- miscellaneous screws
- rubber band
- VCR motor with pulley
- metal L bracket
- wire and zip ties
- variable output power supply
- programmable timer
- wood for base
- electrical tape

Tools used:
- power drill
- drill bits / driver tips
- pliers
- soldering iron





I drilled four small holes on one side of the empty bottle about a half inch apart from each other, the first two 1/3 of the way up and the size and the other two 2/3 of the way up. I then drilled a hole in the center of the cap and in the center of the bottom of the bottle. A straightened coat hangar through these two holes allows the bottle to rotate. I bent the ends down, bent loops, and fastened them to the wood base. I fastened the motor to one side of the L bracket with zip ties and the other side down to the wood base with a screw, making sure the pulley was lined up with the deep grove near the top of the bottle. A rubber band runs around this grove and then to the motor pulley. Flaked fish food is funneled into the bottle. When the motor runs the bottle rotates, agitating the food and causing bits to fall out of the holes in the side when facing downwards. The holes are placed above the feeding door in the tank's cover so the bits of food fall into the tank. The variable output power supply is set to the lowest voltage possible while still providing enough power to agitate the flakes enough to break up and fall through the holes. The programmable timer is set for 5am and 5pm, running for one minute each time, providing enough food for the day. Since the Vitamin Water bottle is large, a decent amount of food can be stored thus allowing the feeder to operate over long periods of time without maintenance or refills. Below is a video of the feeder in action. I manually override the timer to operate the feeder for the video.



This project was very simple and functional. I hope to revamp the design into something that looks better and can be used on a daily basis regardless of whether we are there or not. Thanks for reading and happy tinkering!