I have updated the code on github for the new PCB. 

In this new version there is :

• the pH sensor 
• the EC sensor
• the temperature sensors
• the data sending to ThingSpeak

The entire bluetooth communication routine between an android smartphone and the esp32 is also complete.

This application, which should arrive this week, will allow you to modify the parameters of the tower (such as the time of the cycles, activate or deactivate the sensors, ...)

But most importantly, the EC and pH sensors can be easily calibrated through the application.