# Smart Fish Feeder (ESP32 + MQTT)

An automated aquarium feeder system based on the ESP32. It dispenses food via a motor pulse triggered by Home Assistant and continuously monitors tank temperature.

## ⚡ Features
*   **Remote Feeding:** Trigger a measured feed pulse via MQTT (`tank/feed`).
*   **Temperature Monitoring:** Reports water temp every 10 seconds via MQTT (`tank/temperature`).
*   **Home Assistant Integration:** Fully compatible with HA Dashboards and Automation.
*   **Safe Power Design:** Optically isolated power rails (ESP32 vs Motor) to prevent brownouts.

## 🛠 Hardware List
*   **Microcontroller:** ESP32-D0WD-V3 (DevKitC)
*   **Actuator:** DC Motor (3V-6V) with auger/screw mechanism
*   **Switching:** N-Channel MOSFET (IRFZ44N)
*   **Sensor:** DS18B20 Waterproof Temperature Sensor
*   **Protection:** 
    *   1N5822 Schottky Diode (Flyback protection)
    *   10kΩ Pull-down Resistor (Gate to GND)
*   **Power:** 
    *   USB-C (5V) for ESP32
    *   External 5V/12V DC Adapter for Motor

## 🔌 Wiring & Pinout

**⚠️ CRITICAL:** The ESP32 and Motor Power Supply must share a **Common Ground**, but 5V lines should remain separate to prevent noise/brownouts.

### GPIO Config
| Component | Pin | ESP32 GPIO | Notes |
| :--- | :--- | :--- | :--- |
| **MOSFET Gate** | Left Leg | **GPIO 27** | Use 10kΩ Pull-down to GND |
| **Temp Data** | Yellow Wire | **GPIO 14** | Requires 4.7kΩ Pull-up (if not on module) |

### Circuit Diagram (MOSFET)
*   **Gate (Left):** -> GPIO 27
*   **Drain (Middle):** -> Motor Negative (-)
*   **Source (Right):** -> Common GND
*   **Motor (+):** -> External Power 5V
*   **Diode:** Across Motor Terminals (Silver stripe to +5V)

## 💻 Firmware Configuration

**Dependencies (Arduino IDE):**
*   `PubSubClient` (Nick O'Leary)
*   `OneWire`
*   `DallasTemperature`

**Setup:**
1.  Update `ssid`, `pass`, and `mqtt_server` in `fish_feeder.ino`.
2.  Set `MOTOR_PIN` (Default: 27) and `TEMP_PIN` (Default: 14).
3.  Upload.

## 🏠 Home Assistant Integration

### 1. Manual Configuration (YAML)
Add to `configuration.yaml` to create entities:

```yaml
mqtt:
  sensor:
    - name: "Fish Tank Temperature"
      state_topic: "tank/temperature"
      unit_of_measurement: "°C"
      device_class: temperature
      unique_id: "fishtank_temp_01"

  button:
    - name: "Feed Fish"
      command_topic: "tank/feed"
      payload_press: "pulse"
      icon: mdi:fish
      unique_id: "fishtank_feed_btn"
```

### 2. Dashboard (Lovelace)
*   **Temperature:** Use a `Gauge` card linked to `sensor.fish_tank_temperature`.
*   **Feeder:**