FRIZ ran his air line 900' from his windmill to the diffusers. He's got an alcohol injector on the system, but the level didn't budge all winter and he didn't have a problem with frozen lines.

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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).