Not trying to be a douche, i just want to let people reading this know what Auber told me with regards to the temp probe used in this build..
You can't immerse the tip that deep. This probe is not waterproof at all. Only the very tip (1/8") can be immersed. This probe is designed for measuring metal temperature such as plastic injection mold. The steel braid will rust in water. The water will also get into the tip to cause error reading, and corrode the TC wire. The only thermocouple we have that can be immersed this deep is the WRNK-191 with 10" probe. You should use our PT100S RTD probe for this application. It can be immersed and is much more accurate.
The PT100S rtd he's talking about is completely waterproof (wire included as it has a teflon jacket).