Sorry for my poor English!

You need an Arduino（NANO,MINI,UNO、、、） And a 28BYJ48 stepper

If your fish food's diameter more than 2mm, you will need a little Screw(prt0003)

Arduino Code

//#include "Stepper.h" //#define STEPS 100

Stepper stepper(STEPS, 2, 3, 4, 5);//CHANGE TO YOUR PIN

int previous = 0; long interval = 7200000L;//Interval ,HOW LONG, 7200000L MEAN 2 HOURS unsigned long previousMillis = 0;

void setup() { stepper.setSpeed(80); }

void loop() { unsigned long currentMillis = millis(); if(currentMillis - previousMillis > interval) { previousMillis = currentMillis;
stepper.step(3500); //HOW MUCH } if(currentMillis < previousMillis){ //OVERFLOW CHECK previousMillis=currentMillis; }

}