Here is a tested Arduino project that uses 3 sensor probes as water level indicator with 3 leds and one LCD display + a simple controller that turns on a motor when the water has reached the desired ...

According to [Dr. Tom Lehrer’s] song Pollution, “Wear a gas mask and a veil ... [Ashish Choudhary] married an Arduino with a display and a pollution sensor to give readings of the PM2.5 ...