Motivated by Betta Fish Feeder, this projects uses the basic design by Trevor_DIY and applies new functions to it. Feeding fishes on it's own with a timer set, this re-moded version adds more useful tools to the user, such as how many spins until a refill for the food is needed, and a warning when it is actually empty.

Supplies

Arduino Leonardo
Arduino power adapter (or USB adapter)
Motor driver and stepper motor (28BYJ-48)
Hard Card board
Hot glue
Fish tank
Betta fish pellets
5 light bulbs,
10 crocodile clip wires
resisters
double-output wires

Step 1: Setting the Motor

Plug the stepper into the motor driver with the white connector.
Connect the Arduino output pins 8, 9, 10, 11 to the motor driver input pins 1N1, 1N2, 1N3, 1N4 respectively.
Connect the Arduino power pins GND and 5V to the motor driver power pins - and + respectively.
Connect the Arduino USB port to your computer and start the Arduino software.

Step 2: Cutting the Wheels and Assemble

3D printed wheels, used by the original creator, is a much faster choice with better quality. However, if such thing is far to reach, using card board to cut is also a viable choice.

Cut two similar circles.
Cut the first into a axis-wheel like shape, with a small hole in the center.
Cut the second with a hole in the center, and an another small hole next to the center.
Glue the second wheel on the bottom, on top of the motor, but not connected to the motor.
Put the first wheel on top of the second, with the center hole connected to the motor.

Step 3: The Lights (add-on's in This Project)

What's different from the original project, is the reminder feature installed in this project.

4 light bulbs (white) indicates the number of spins left before the food is emptied. For example, 3 bulbs bright means three spins left, while 1 bulb bright means one spin left.
The red light bulb with turn on once all spins are used, as a warning for the user to refill the food.

Install the 4 light bulbs to 8, 9, 10, and 11 respectively, with resisters, wires, GND and 5V input/output installed etc.
install the red light bulb to 13