Originally Posted by Commander
I currently have regular 3/8 black poly lines running from the compressor on top of the ground about 20 ft to the pond edge where it transitions to 3/8 weighted line. So I should plan this summer on trenching that line and replacing it with one inch poly or even PVC? I'm guessing I would need to go below the frost line, which is pretty deep here in Western Iowa.

Once the line is in the pond below the ice thickness depth you don't have to worry about it freezing. Here the frost line is 38" IIRC, we only place them about 12" below grade. You can buy low pressure black poly pipe like they use for sprinkler systems and running water from the well to the house. The less connections you have under ground the better.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).