You can make PVC trees from 3" thinwall ag drain pipe, and use 1/2" to 1" rolled poly tubing for the branches. If you search, you should be able to find the poly tubing for $0.10/foot or so.

www.hoosierpondpros.com

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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).