Hydroponics Controller: Pumps, Lights and Alerts
Schedule grow lights and nutrient pumps, monitor climate and get alerts when something drifts.
Indoor growing is all about consistency. A Pi can run light and pump schedules on low-voltage gear, log the environment and warn you before a problem kills a crop.
Water and electricity: keep all electronics above and away from reservoirs, use drip loops on cables and protect outlets with GFCI.
Video tutorial
Video by hydrosys4 raspberry, embedded from YouTube. The written steps below are our own and match the parts list.
Mission steps
Choose low-voltage gear
Use 12 V LED grow lights and 12 V pumps switched by the relay module. For mains-powered equipment, use certified smart plugs controlled by Home Assistant instead.
Wire the relays
Relay inputs to GPIO17 and GPIO27. Many relay boards are active-low — gpiozero's active_high=False handles that.
Schedule with code
Lights 16 hours on, pump 15 minutes every hour — the script below does it without cron.
Monitor the climate
Log temperature and humidity with the BME280; add analog pH or EC probes through the ADS1115 when you are ready.
Alert
Send a phone notification (ntfy) when humidity or temperature leaves your target range.
Code
from gpiozero import OutputDevice
import time, datetime
light = OutputDevice(17, active_high=False, initial_value=False)
pump = OutputDevice(27, active_high=False, initial_value=False)
while True:
now = datetime.datetime.now()
light.value = 6 <= now.hour < 22 # 16 h photoperiod
pump.value = now.minute < 15 # 15 min every hour
time.sleep(20)Tip: test every script on the bench before installing it in a moving machine.
Questions
Are pH sensors worth it?
Yes for serious growers, but cheap probes drift and need regular calibration with buffer solutions. Start with manual test strips.