Automate your aquarium or hydroponics fertilization with this Smart DIY 4-Channel Dosing Pump! Fully integrated into Home Assistant via ESPHome, this project offers precise liquid dosing, easy calibration, and real-time usage tracking.

✨ Features

• 4 Independent Channels: Control up to 4 different liquids (fertilizers, additives, etc.).
• Smart Home Ready: Fully configured for Home Assistant via ESPHome.
• Precise Dosing: Set daily doses in milliliters (ml) directly from your HA dashboard.
• Built-in Calibration: Automated 60-second calibration function to ensure accurate dosing.
• Liquid Tracking: Persistent tracking of total dosed liquids, so you know exactly when to refill your containers.
• Manual Override: Physical push buttons for easy manual priming and flushing of the tubes.

🛠️ Bill of Materials (BOM)

• 1x ESP32-S3 WiFi/BLE Module (mounted on a Protoboard for easy wiring)
• 4x Kamoer NKP Low-Flow Peristaltic Pumps (12V DC, 3x5mm tubing)
• 1x 4-Channel MOSFET Module (PLC amplifier/driver board)
• 8x M3 Heat-set Threaded Inserts (Ruthex or similar)
• 2x M3 x 15mm Screws
• 6x M3 x 10mm Screws
• 1x 12V Power Supply + suitable DC Jack Adapter

⚡ Power Supply & Safety Concept

In my default setup, the ESP32 is powered continuously via USB to maintain a stable connection to Home Assistant. For safety reasons, the 12V power supply (which powers the pumps via the MOSFET) is connected to a smart plug and is only turned on during the actual dosing process.

💡 Optional: If you prefer a single-cable solution, you can easily integrate a step-down buck converter (12V to 5V) inside the case to power the ESP32 directly from the 12V supply!

💻 Software / Firmware

The provided ESPHome YAML code contains all the necessary logic. It handles the math for converting milliliters to pump run-times based on your calibration, saves total consumption data directly to the ESP's flash memory, and sets up all the buttons, sliders, and sensors you need for a beautiful Home Assistant dashboard.

Happy Making & Happy Plant Keeping! 🪴🐟