I have this good Hailea HC-500A waterchiller:
Here is some specs:
Here is the "face" of the controller:
It's a 1/2 HP compressor, 790W of cooling capacity.
It can chill down the water to a lower 3°C.
Is there any way that I can "cheat" the controller to reach sub-zero temps?? About -3° to -5°C is just fine.