Pretty cool thread and something Im interested in also. I have a friend up here that keeps a cold water 150 stalked with local items. Its basically a tidewater tank but very cool. He has it down now but it is so easy to get up and run. A good chiller is needed to push it down to around 45-50*. Ive seen him keep lots of different things including live King Crab waiting for the pot
and black bass.
I plan on trying something in the future but instead of a chiller I want to try a heat exchange using buried plastic line and a good pump. Something that was deep enough to not freeze in the winter. If I can get a handle on my other projects I would be able to start. Love to see some picts of your setups.