This design is part of my Plant Grow Tent Project:
https://www.thingiverse.com/thing:6724085

Auto Watering System for Grow Tent (Version 4.6.1) MODIFICATION

This design is a modification of: 4.6.1 Auto Watering for Grow Tent.

Here will you find the .pdf handout:
https://drive.google.com/drive/u/1/folders/1B2OIvdmnxRqS1MRcuJaII8CSyUZvPqu5

For this design, I took the PUSH approach. That means water is pushed via a timer at a defined time through the watering ring onto the soil of the plant. Since the watering ring disperses the water, it will drip and be partly absorbed. When water finally drips through the pot and runs out under it, the water will reach the water level sensor. As soon as this happens, the pump is turned off. This way, the plant will be watered more like the ordinary way. In the garden, I also just water the plants until the water runs through.

The other design works fine too. The other approach was the PULL approach. There, I used a humidity sensor to determine when the soil becomes too dry and new water is needed.

I feel the push approach is more simplistic. One does not need to bother where to place the sensor, and one can also use one big drip tray for several plants and thus just use one watering system. If one chooses to do so, it would be best to use the same length of water hose from T-sections in order to ensure that every plant gets an equal amount of water.

I would use a timer that is set about one hour before the light inside the tent turns on, so maybe at 5-6 o'clock. That is the time when normally dew occurs outside. Since the lamp will power on after the plant has soaked all the water it needed, the rest will be absorbed by the air as the temperature rises with the waste heat of the lamp. This way, I guess it will have the lowest impact on high air humidity levels inside the tent.

I hope you like this approach. Which one do you prefer?
Happy growing!

Update: 2024-12-23 Sensor_Mount_2.0 – Anti Galvanic Corrosion

This update addresses the issue of galvanic corrosion in water level sensors. To prevent degradation, I replaced the final wire segment with solid 1.5 mm² copper cables. These are more durable, easier to inspect, and simpler to replace compared to stranded wires. Additionally, the updated Sensor_Mount_2.0 provides better stability and supports the use of the improved wiring system.

Durability: Solid copper wires eliminate the risk of corrosion at the contact points.

Ease of Maintenance: Improved mount design allows for quick inspection and wire replacement.

Enhanced Usability: Tap water or naturally dirty water works perfectly, but crystal-clear rainwater may not conduct properly for testing.