I found out the hard way that it's more expensive trying to put a valve on corregated than PVC pipe. I'd lean that way and use what the pocketbook will allow, stronger is always better I say!

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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).