Sure it would work without the peltier chip in an open bath.  You will lose fluid over time though if you don't condense it.

I am using a much bigger box for my final unit and hopefully I can fit 20-25 Neptune cards in the box with a very large radiator.

I will add them 5 at a time until I can't dissipate the heat anymore.

Here is the video - https://www.youtube.com/watch?v=gk3Vydo-L58