There's a guy in Northern Europe that burried a 100 gallon tank 15 feet under...
The advantages of externally(outside) cooled systems (versus inside i.e. within the case) is that it will be very quiet.
The disadvantages include bigger pump, work involved, and sometimes cost. Also, the temperatures achieved will vary with the season, which is fine if you're only water cooling, but maybe no so good if you are using a Peltier.
A truck heater core, huh? What size?
