The Adafruit DIY sous vide guide was an excellent starting point for this project. They give a great deal of information about several of the components I used, so I’ll mostly just refer people to their site. I did end up getting rid of the PID controller, it was more complicated than it needed to be especially with both heating and cooling (with very different properties). Another plus of building this water bath was that I had a sous vide along the way. I made a few steaks, and they were excellent!