Don't know if this would work (but it is what I plan on doing with my system when I get it up and running).  I'm going to have a sump tank burried 4-6 feet down (where the temperature stays at a constant 50-55 degrees and has the effect of thermal cooling/heating) and have it pumped up to the surface of my fish tank that is burried half in the ground.  Then i'm going to siphon the water off the…