So I'm assuming u have the kit with all three probes
this is how I did it and in this order:
Sensor78-2 k,0.1 (don't expect anything in the console it will return {"Sensor":""})
Sensor78-2 K,? (this will tell u what your probe is set to, it will return a result on console)
if that goes by smoothly the rest is simple.
started with the ph. and have 2 windows open. one with console and the other with the tasmota home page with the probe readings.
PH
Start with the PH7 first, set the probe in solution and wait for the reading to stabilize then send this command in console. The reading will reset and will calibrate to 7
Sensor78-1 cal,mid,7 (reading adjusts)
Then PH4 same as above and don't forget to rinse the probes as you switch solutions
Sensor78-1 cal,low,4 (reading adjusts)
followed by PH10 High
Sensor78-1 cal,high,10 (reading adjusts)
EC
First calibration must be dry. Nothing will show or happen here in either window
Sensor78-2 cal,dry (no change on reading)
then Low ( unlike the PH when u calibrate the low the reading on the second window WILL NOT change! It will change once u calibrate the last high point in thee next step)
Sensor78-2 cal,low,84 (no change on reading)
EC HIGH
Sensor78-2 cal,high,1413 (reading adjusts)
once u send this command on console u should see the EC reading change similar to the PH calibration
That's it you are all done
Hope this helped and worked out. I spent way to much time scratching my head to get it done. I'm still new to all this
If u want the scripts to do it through Home assistant and MQTT let me know I got it working as well
sorry for the delay had a hectic work week