The hydroponic system I use is based on the Kratky method which allows any vegetable to grow in the system without the need for pumps that re-circulate the water or oxygenate it since the plant begins to absorb the nutrients from the water, consuming the level of it thus achieving a space that allows it to absorb oxygen from the environment.
    
For simulation and practical purposes I created this prototype including a re-circulating pump and sensors to study various hydroponic techniques more closely.        

The prototype allows to automate the start and end of the re-circulation of the water to distribute the nutrients and allow all the plants to absorb them equally by means of a 5v submersible pump. It also has a lamp with 15 LEDs (12 red 3 blue) powered at 12v by a DC-DC 1A step-up source.       

To obtain information on water quality, I measure its parameters (PH and TDS) with analog sensors connected to the inputs of the Fischertechnik TXT Controller and the temperature obtained by the I2C BME680 environmental sensor.

See also: Mini Hydroponic System v2