UGF Heating Alternative

I was thinking about UGF and came up with the following: What about 
putting a spaced coil of hard PVC tubing(say 1/8 inch diam) under 
the substrate and pumping warm( or hot) water through it in a closed 
loop system? Any thoughts on this??
"A Bad Day Fishing Is Better Than A Good Day At Work"
1:  Macaw at tiac_net
2:  robert_s_woolley at ffn_mhv.net
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