Introduction: How to Build an Automatic Fish Feeder

This instructable was created in fulfillment of the project requirement of the Makecourse at the University of South Florida (

Materials needed:

  • Arduino Uno R3
  • Female to Female Wires
  • Breadboard
  • IIC 1602 LCD
  • IIC Cable
  • IR Receiver
  • IR Remote
  • 10k Resistor
  • SG90 9G Servo
  • 1/8 inch thick Acrylic (at least 8"x
  • 3D printing plastic
  • 5 #10x3/4" screws (for acrylic and plastic parts)
  • 4 #4-40x1/2" screws with nuts (for LCD screen)
  • 4 M3X5 screws (for Arduino)
  • Super glue (I used Loctite Professional Liquid)
  • AC/DC wall adapter (to plug the Arduino into the wall)
  • Hot glue sticks

Equipment needed:

  • 3D printer
  • Screwdriver
  • Computer with Inventor
  • Laser Cutter
  • Drill and bits
  • Hot glue gun

Step 1: Print Parts

Print the .stl files attached with a 3D printer; I used a MakerBot with 100 micron resolution.

Step 2: Program Arduino

Load the attached Arduino sketch onto the Arduino. If you are using a different remote than I used, you will have to change the codes in the case structure of the sketch. You will do this by opening the serial monitor while the Arduino is plugged in and the IR sensor is connected. Press each button you intend to use and replace my codes with the codes you see.

For help, visit

Step 3: Cut Arcylic Lid

Cut the file titled Acrylic Cover.dwg and raster the angelfish image if desired. I used a 100W laser cutter, the settings were as follows:

  • Vector cut - 2 passes, 30 power
  • Raster - 27.5 power, 80% speed

Step 4: Electronics Assembly

Assemble the electronic components according to the schematic above. The resistor should be 10k. Make the project neater by using only the power rail of the breadboard and soldering the rest or solder everything.

Step 5: Final Assembly

  1. Use 2 #10x3/4" screws and the drill to attach "Box part 1" to "Box part 2"
  2. Feed the AC/DC adapter through the hole in the right half of the box. Plug this into the Arduino.
  3. Mount the Arduino with the 4 M3X5 screws.
  4. Super glue the "Lever arm" that you printed to the arm that came with the servo.
  5. Insert the servo motor into the rectangular cutout on the bottom of the right half of the box. Orient it so that the shaft is farther left. Secure the motor with hot glue.
  6. Attach the servo arm to the servo, using something sturdy and thin will help with this process.
  7. Using the 4 #4-40x1/2" screws with nuts, mount the LCD screen to the acrylic lid. Make sure the LCD screen faces outward and that it's on the right side of the box.
  8. Double check that all wires are still attached. Use the remaining 3 #10x3/4" screws to secure the acrylic lid to the box.
  9. Fill the left side of the box with fish food.