Fish Tank Automatic Feeder (for small to medium fish, remote and timed feeding)

This project draws inspiration from the model of community expert @醒了 and has been redesigned and optimized based on it, specifically for the automatic feeding needs of household small to medium-sized fish tanks

This electric feeder is suitable for 0.8 - 2.0 mm pellet fish food and can be used with a timer to achieve timed and quantitative feeding, effectively solving the problem of short-term outings or daily forgetting to feed

I. Design Features

1. Feed Compatibility
   • Suitable for 0.8 - 2.0 mm pellet feed, ensuring smooth dispensing without clogging
2. Power Unit
   • Uses an N20 geared motor, small in size, high in torque, and stable in operation
   • The power compartment is changed to a square hole design, making it easy for the N20 motor to be inserted and securely fixed, preventing the motor from loosening as the screw rotates
3. Feeding Mechanism
   • Added a 3D printed feeding screw, capable of stable and uniform delivery of fish food, ensuring consistent dispensing volume each time (Pitch can be adjusted to optimize for feed size selection)
4. Base Optimization
   • Supports 3 - 12 cm fish tank thickness, compatible with more types of fish tanks
   • Added M6 screw fixing holes to ensure stable and non-shifting equipment installation
5. Modular Design
   • The base and main body are magnetically connected, using 20 × 5 mm neodymium strong magnets, for easy quick disassembly and arbitrary adjustment of discharge direction
   • Enlarged food reservoir, one full refill can last for approximately two weeks (adjust according to the number of fish)
6. Electronic Control Section
   • Power specifications: DC 3V 1A adapter, 1.5m cable length, with female connector
   • Timer control: Uses an eWeLink Wi-Fi timing switch, set to inching mode, to achieve automatic feeding

II. Parts List

3D Printed Parts

• Electric Fish Feeder - Base
• Electric Fish Feeder - Main Body
• Electric Fish Feeder - Screw Rod
• Electric Fish Feeder - Food Bin
• Electric Fish Feeder - Back Cover

Recommended materials:

• PLA+ (easy to print, low cost)

• PETG / ABS (better high temperature resistance and moisture resistance)

   

• For students who find it inconvenient to print ABS, all printed parts of this model can currently be printed for free through JLCPCB

Electronic/Mechanical Parts

• N20 Geared Motor ×1    (Recommended 50 RPM)             RMB 5 - 8
• Power Adapter: 3V 1A (1.5m with female connector) × 1                RMB 3 - 5
• eWeLink Wi-Fi Timing Switch × 1                                            RMB 20
• Neodymium Magnet (Round) 020 × 5 mm × 2                              RMB 4
• Screw M6 × 35mm × 1                                                    RMB 1

    Total Cost : RMB 30  ~  35

III. Installation Steps

1. Print all 3D model parts
2. Solder the N20 geared motor to the female connector part of the power adapter cable
3. Insert the N20 geared motor into the square hole from the rear power compartment of the main body to fix it
4. Insert the feeding screw into the front feeding compartment of the main body, and insert it into the motor shaft, ensuring smooth rotation
5. Use 502 glue to fix the neodymium magnets separately on the base and the main body, then magnetically attach the main body to the base
6. Install the base, fixing it to the fish tank edge with an M6 × 35mm screw
7. Connect the power to the eWeLink timing switch, and test if the power-on operation is smooth

IV. Usage Instructions

• For first-time use, it is recommended to test with a small amount of fish food first, and adjust the power-on time of the timer's "inching mode" to control the dispensing quantity
• It is recommended to keep the food bin dry to prevent moisture caking
• Regularly clean the feeding screw and outlet to ensure smooth operation
• A full food bin can meet approximately two weeks of feeding needs (depending on the number of fish and feeding frequency)