Electric "Hot Tank" for wort souring

This is essentially kettle souring, but I wanted to have a dedicated rig for it. I started planning by looking at what makers were doing with DIY Sous Vide setups. I cobbled together my control box from this article, and I'm working on assembling my element and preparing the bucket I'm going to use as a fermenter.

I'm posting just to share and see if anyone had any tips, or corrections to this method. (I'm not an electrician by any means)

Here is the electrical diagram from the site. Mine is almost identical to this, except my switch is on the "neutral", not the "hot" lead. I'm not sure how much that matters, as the device I built works just fine.



My plan for the bucket is to have a probe mounted somewhere about the middle of the liquid, and the element mounted near the bottom. As for the pump, I'm not sure what to do. I did purchase a small submersible pump I could use for agitation, but that's one more thing that needs to be cleaned and sanitized and this setup is already a bit on the tricky side. I may start by just seeing how well I can heat a bucket of water without the pump.

A big question I had was about grounding the liquid in the tank. No one in the Sour Vide DIY articles I looked at seemed concerned with it. But I know that it's standard practice around here. I'm not sure what to do, as the heating element I got has no ground, so I didn't bother to ground anything in my control box. So should I run a ground lead into the bucket somehow?

Thanks!